Giao Trinh Hai Ha

8/8/2019 Giao Trinh Hai Ha

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BO GIAO DUC VA AO TAOAI HOC KY THUAT CONG NGHE

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GIAO TRNH THC HANH

HOA MOI TRNG

Bien soan: ThS. INH HAI HABien soan: ThS. INH HAI HABien soan: ThS. INH HAI HABien soan: ThS. INH HAI HA

TP.HO CH MINH,TP.HO CH MINH,TP.HO CH MINH,TP.HO CH MINH, thangthangthangthang 01010101 nam 200nam 200nam 200nam 2008888(Lan 1)(Lan 1)(Lan 1)(Lan 1)


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Thc hnh Ha Mi Trng Bin son: ThS inh Hi H

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LI NOI AULI NOI AULI NOI AULI NOI AU

Giao trnh thc hanh Hoa Moi Trng c bien soan cho sinh vien khoa Moitrng va CNSH trng H KTCN.

Hi vong giao trnh nay se giup cho cac ban sinh vien co c nhng kien thc vephan tch cac ch tieu trong nc cap, nc thai, ay se la nhng kien thc ganlien vi cong viec tng lai cua cac ban. Do bien soan lan au nen khong tranhkhoi thieu sot, mong nhan c y kien ong gop cho lan tai ban sau.

Tp HCM, Tet Mau T, 2008.

Th.S inh Hai HaEmail:Email:Email:Email: [email protected]@[email protected]@yahoo.com


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LAY MAU VA BAO QUAN MAULAY MAU VA BAO QUAN MAULAY MAU VA BAO QUAN MAULAY MAU VA BAO QUAN MAU

1. Gii thieu chung1. Gii thieu chung1. Gii thieu chung1. Gii thieu chung

Thc te khong the e ra cu the nhng chi tiet co the ap dung cho viec lay

mau, va ket qua phan tch cung khong the nao phan anh ung hoan toan chatlng mau nh thc. ieu nay phu thuoc vao muc ch cua viec lay mau vaphng cach khi tien hanh phan tch. Nhng chi tiet khac lien quan en tngphng phap rieng se c e cap en trong moi bai. Phan nay ch gii thieukhai quat nham ap dung trc tien oi vi cac phep phan tch khoa hoc.

Thc chat cua viec lay mau la thu nhap mot phan vat chat trong mot thetch va u, x ly va van chuyen ve phong th nghiem kp luc khi chat lng maucha thay oi. Muc ch tren nham gi c t le tng quan gia nhng cau tac trng trong mau va nguon. Mau sau o c bao quan sao cho nhng thayoi neu co cung khong ang ke trc khi tien hanh th nghiem.

Ngi lay mau phai chu trach nhiem chnh ve chat lng mau cho en khimau c gi en phong th nghiem e phan tch. Thong thng nhng cong vieclien quan en nc va nc thai, phong th nghiem eu cong bo s hng danhoac quy nh ro ve ky thuat lay mau, hoac phai c thao luan vi ngi se trctiep s dung ket qua xet nghiem. Nhng buoi hop nh the rat can thiet v giupnhieu y kien ve cach chon mau, phng phap phan tch cung nh se gi nennhng van e c ban trong khi giai ap cac thac mac lien quan en mau.

2. Nhng ieu2. Nhng ieu2. Nhng ieu2. Nhng ieu can lu ycan lu ycan lu ycan lu y

Mau phai ap ng ung theo cac yeu cau cua chng trnh lay mau vac bao quan, tranh moi nguon nhiem ban hoac s phan huy co the xay entrc khi a ve phong th nghiem .

Phai suc ra t nhat ba lan bnh lay mau bang chnh nguon nc trc khilay mau, tr trng hp bnh a c x ly bang hoa chat bao quan hay tac chatkh clo. oi vi nhng mau phai van chuyen xa, khong nen lay qua ay macha lai o 1% dung tch bnh, khoang trong nay e phong h s dan n nhiet.Tuy nhien ieu nay tuy thuoc vao cac xet nghiem can lam. Hau het cac trnghp xet nghiem cac chat hu c, bnh phai c lay ay tran hoac co luc c

pha tron va cha lai mot khoang trong vi muc ch lam thoang va xao tron nhtrng hp xet nghiem vi sinh.

S than trong luon can thiet, nhat la khi mau co chat hu c hoac e xetnghiem cac vet kim loai. Nhieu cau t oi khi hien dien ham lng rat nho (0g/l) do o mot phan hoac toan bo chat ay co the b mat han neu lay mau va baoquan mau khong ung cach.


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Mau tieu bieu cho nhieu nguon co the tao c t viec pha tron cac maulay nhng thi iem khac nhau hoac tng a iem khac nhau. Chi tiet laymau tat nhien thay oi theo ieu kien a phng, khong co mot khuyen cao cuthe ap dung cho moi trng hp.

Muon co nhieu d kien hn va cung e tranh s kho hieu tai cac iem cc

tr (toi a va toi thieu) viec phan tch nen thc hien tren nhieu mau rieng bietthay v s dung mau hon hp.

S than trong luc lay mau khong ngoai muc ch am bao ket qua phananh ung thc chat mau. o uc chat l lng va chat kh uc, nhng thay oihoa ly do thong thoang hay xay ra trong qua trnh ton tr la nhng yeu to quantrong anh hng en ket qua. Can lu y ac biet cac khau nghien, pha tron, sangloc mau, chuan b cho viec phan tnh cac chat dang vet, nhat la cac vet kim loaiva vet cac chat hu c. Trong mot vai xet nghiem nh ch, hau qua nhiem ban tcac qua trnh tren eu khien ket qua khong con chnh xac. Can chu trong en cacch tieu xet nghiem e co cach x ly thch hp cho tng mau. Kch thc va banchat cac chat gay uc kem cac yeu to khac eu co tac ong nhat nh tren ketqua.

Thc te khong the e ra mot phng sach co kha nang bao quat moi tnhhuong va viec chon ky thuat lay mau phai do th nghiem vien quyet nh. Trennguyen tac, cac chat l lng c tach bang cach lang, ly tam hay gan loc. Nhngthong thng th o uc thap co the bo qua neu kinh nghiem cho thay no gay anhhng khong ang ke tren phep nh phan trong lng va nh phan the tch,cung nh co the hieu chnh c trong phep so mau (la phng phap de b nhieunhat). Tot nhat nen ghi ro mau a loc hay cha loc. e o ham lng chat ran

tong cong (TDS), khong c phep loai bo cac chat l lng ma phai tuy nghi xly cho thch ang. Phai ghi chep nhng chi tiet lien quan en viec lay mau, cachtien nhat la dung cac the, nhan in san moi e muc sau o nh kem cho tngbnh. Can ghi chep ay u, ro rang ten ngi lay mau, ngay gi, nhiet o nc vanhng d lieu khac nh thi tiet, mc nc, dong chay, tram quan trac thi iemgi mau. Ch th a iem lay mau ro ret tren ban o, tot nhat nen anh dau cacv tr bang coc, phao hay mo ta cac ac iem hay b e ngi khac van nhandien lai de dang luc can ma khong phai van dung lai tr nh hay lan tm qua lihng dan, ac biet khi mau lien quan en viec tranh tung, phai s dung en hos lu tr (chain-of-custody) e truy cu mau t khi lay cho en luc co c ket

qua sau cung.Mau khi lay nhiet o cao phai c lam nguoi trong cung ieu kien ap

suat. Neu muon lay mau t he thong phan phoi, nen xa voi chay t do trong motthi gian ngan am bao mau the hien ung chat lng nguon, van toc va lulng xa tuy thuoc vao ng knh va chieu dai ong. Tng t khi lay mau ncgieng, hay e gieng hoat ong t do mot thi gian en khi chac rang mau a ai


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dien c ban chat nguon. oi khi muon xac nh nguon bo cap, phai ieu chnhbm mot lu lng xac nh, ghi lai lu lng bm va lu lng bo cap.

oi vi nc song, nc suoi, chat lng nc thay oi theo o sau, dongchay va khoang cach t v tr lay mau en b. Lay mau hon hp theo o sau mat cat en tan ay tai v tr gia dong, hoac doc theo mat cat dong chay cung

o sau trung bnh. Cach lay mau hon hp tuy thuoc vao tnh chat, lu lng vache o thuy lc cua dong chay. Neu ch can lay mau bat ky, nen lay mau osau bat ky, nen lay mau o sau trung bnh tai v tr gia dong.

oi vi mau cac ho va ham cha, khi lay mau phai lu y en tac ongcua ma, lng nc chay tran tren be mat, gio, yeu to phan tang theo mua Tat ca eu co the gay anh hng en chat lng nc. Viec chon o sau, tan solay mau con tuy vao ieu kien a phng va muc ch khao sat. Chu y tranh lpvang be mat.

oi vi mot vai thanh phan can khao sat trong mau, v tr lay mau gi motvai tro vo cung quan trong, tranh cac vung xao tron manh v de lam that thoat cacchat de bay hi trong o co the co ca chat oc. Tai nhng vung nh gan apnc, nguon co khuynh hng phuc hoi nhe, thay oi ham lng chat l lng.Thong thng, mau c lay vung tnh, di mat thoang. Neu co yeu cau vemau hon hp, phai than trong oi vi cac thanh phan de that thoat khong phai doqua trnh lay mau ma v viec x ly khong ung cach. Th du: khi tron lan, thay vs dung ong si phong cho chay t t, mau lai c o ao mot lan, ay la nguyennhan lam giam ham lng cac chat de bay hi ma ngi lay mau co the hoantoan tranh c. Cung can lam lanh mau e giam thieu s bay hi.

Ch s dung cac mau thch ng vi cuoc khao sat (hoac nhng mau nam

trong chng trnh lay mau), khi lay mau nhng ieu kien khac nen ghi chep lairo rang va ay u moi chi tiet. Thong thng, trong ban bao cao cung can mo taphng phap th nghiem muc ch cuoi cung.

3. Bien phap an toan3. Bien phap an toan3. Bien phap an toan3. Bien phap an toan

V trong mau co the co nhng thanh phan oc chat nen phai ap dungnhng bien phap e phong hu hieu trong suot qua trnh lay va x ly mau. occhat co the tham qua da, bay hi tham nhap vao phoi, cung khong loai tr tnhtrang ngo oc qua ng tieu hoa. Cac phng tien phong ho pho bien la: gang

tay, knh bao ho mat Trong phong th nghiem, khi tiep xuc vi chat oc de bayhi, nhan vien phai trang b them mat na chong hi oc ca nhan va ch m cacbnh mau nghi ng co hi oc ni vang ngi, thong thoang tot hay trong tu hutma thoi. Tuyet oi khong c at thc pham gan mau hay trong phong tr mau.Luon ra sach tay trc khi tiep xuc vi thc an.

oi vi chat hu c de chay, can phai ap dung cac bien phap an toan thchnghi. Khong c phep hut thuoc gan mau, ni cha mau cung nh trong phong


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th nghiem. Canh giac vi cac tia la, ngon la hay nguon nhiet qua nong. Trongphong kn nh phong lanh, phong tr mau, phaI lu y en cac tiep iem cua congtac en, may ieu nhiet, bo phc hp s dung ien la nhng ni co the gay ratia la ien, nguyen nhan gay ra nhng vu chay no.

Khi cha tin tng vao mc o an toan, moi bien phap e phong rat can

thiet, phai quan tam en van e huan luyen ve an toan lao ong. Tuy nguonnhiem ban ma co bien phap phong ho y te nghe nghiep khac nhau.

4.Cac loai mau4.Cac loai mau4.Cac loai mau4.Cac loai mau4.1. Mau bat ky hay mau ca biet : (Grab or Catch Sam4.1. Mau bat ky hay mau ca biet : (Grab or Catch Sam4.1. Mau bat ky hay mau ca biet : (Grab or Catch Sam4.1. Mau bat ky hay mau ca biet : (Grab or Catch Samples)ples)ples)ples)Khi mau c lay vao mot thi iem, mot v tr nhat nh, noi cho ung

mau ay ch the hien c chat lng nguon vao thi iem va tai v tr o ma thoi.Tuy nhien cac thong so lien quan en nguon va cac khu vc khao sat c bietro trong suot thi gian tiep can, chat lng mau luc o c xem nh kha nangtieu bieu cho nguon trong khoang thi gian o hoac cung co the bao gom cho cakhu vc o hoac cung luc bao gom ca hai yeu to tren ch khong rieng mot. trongtrng hp tren, mau bat ky cung co the ai dien ac tnh cho dong chay motcach hoan hao, th du : nh vi nguon nc cap, nc mat. oi luc, phng phaplay mau bat ky cung c ap dung cho ca trng hp nc thai.

oi vi nguon c biet ro la chat lng lien tuc thay oi theo thi gian,nhng mau ca biet c lay trong tng khoang thi gian thch hp va phan tchrieng se cho d lieu ve nhng bien oi trong pham vi gii han. Tan so lay mauco the thay oi theo chu ky t 5 phut ti 60 phut hoac co the keo dai hn. Trongmot he thong giam sat, chu ky lay mau co the vt tren ca thang khi nghien cu

cac chuyen bien theo mua. Trng hp chat lng mau thay oi theo khong gian,mau se c chon thi iem thch nghi.oi vi chat mun, bun va nc thai, bun ven b can phai can nhac khi

chon phng phap lay mau, nhng phai that than trong e lay mau cho phu hpvi muc ch can thiet.

4.2 Mau hon hp : (Composit Sample)4.2 Mau hon hp : (Composit Sample)4.2 Mau hon hp : (Composit Sample)4.2 Mau hon hp : (Composit Sample)oi vi nhieu trng hp, thuat ng mau hon hp c dung e dien ta

s tron lan cac mau ca biet lay nhieu iem khac nhau tren cung 1 v tr.Mau hon hp thch hp cho viec khao sat cac ham lng trung bnh, th du

nh trong cach tnh tai trong hay hieu qua cua cong trnh x ly nc thai. Neu

phai chon la gia viec phan tch hang loat mau, sau o tnh gia tr trung bnh roisuy ra tong lng th mau hon hp van co c tnh tieu bieu, hn na con giuptiet kiem cong sc va chi ph cho phong th nghiem. Trong nhng trng hp cuthe, mau hon hp tieu bieu cho mot ca lam viec, cung co the cho mot chu kyngan hn nh thi gian mot lan van hanh maytat ca eu thch hp. e anh gianhng hieu qua, bien ong rieng biet hay cac lu lng that thng th cung chcan lay mau hon hp trong suot thi gian s viec xay ra cung u .


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Muon xac nh cac thanh phan hay cac yeu to ch th nhng thay oithng gap trong ham cha th khong nen dung mau hon hp. Trong trng hpnay, cac mau rieng le (individual sample) se phu hp hn. Sau khi lay mau, viecxet nghiem can phai thc hien ngay oi vi cac ch tieu sau: pH, nhiet o, khhoa tan, sulfua hoa tan, clo dS thay oi cac thanh phan nh: oxi hoa tan, kh

carbonic t do trong nc, pH, nhiet o co the la nguyen nhan keo theo cac thayoi sau xa lien quan en cac chat vo c: sat, mangan, o kiem, o cng.

Tom lai, loai mau nay thng c dung cho viec xac nh thanh phan tthay oi trong ieu kien lay mau va bao quan mau.

Moi mau rieng le c lay trong mot chai rieng mieng rong 35mm, dungtch khoang 120ml. Tuy ieu kien hien trng, viec lay nhng mau nay c thchien hang gi, hoac na gi tham ch co luc 5 phut mot lan. Neu co tac chat baoquan, nen them vao mau sau khi va lay.Viec tron mau c thc hien trong mot bnh ln co dung tch 2-3 lt u e phantch cac thanh phan trong nc cong, nc thai, hoac t ong thoat nc.

Khong nen s dung cac dung cu lay mau t ong tr khi ap dung c ayu cac phng phap bao quan. Tat ca dung cu phai c ra sach hang ngay etranh s phat trien sinh hoc va cac chat lang ong khac.

Thnh thoang cung can phan tch tren mot mau rieng le neu xet thay can.

5. Phng thc bao quan mau5. Phng thc bao quan mau5. Phng thc bao quan mau5. Phng thc bao quan mauPhng thc bao quan mau nc theo ch tieu phan tch c trnh bay trong bangsau :

Bang 1:Bang 1:Bang 1:Bang 1: Phng thc bao quan mau ncCh tieu phan tchCh tieu phan tchCh tieu phan tchCh tieu phan tch Phng thc bao quanPhng thc bao quanPhng thc bao quanPhng thc bao quan

Thi gian ton trThi gian ton trThi gian ton trThi gian ton trtoi atoi atoi atoi a

o cng (hardness) Khong can thietCalci (Ca2+) Khong can thietCloride (Cl-) Khong can thietFloride (F-) Khong can thieto dan ien 4oC 28 gio acid, o kiem 4oC 24 giMui 4oC 6 giMau 4oC 48 giSulphate 4oC; pH


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Carbon hu c 2ml/l HCl, pH12, 4oC, trong toi 24 giPhenol H2SO4, pH


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DDDDUNG DCH CHUANUNG DCH CHUANUNG DCH CHUANUNG DCH CHUAN1. AI CNG1. AI CNG1. AI CNG1. AI CNG

Trong qua trnh phan tch nc va nc thai thng gap nhieu dung dchchuan ma nong o ghi di hnh thc so hu t thay v so thap phan hay songuyen. S viec tren c giai thch bi hai ly do:

Ket qua bao cao: Cac so lieu c yeu cau ghi the nao e ngi thiet ke(thng la nhng ngi khong chuyen mon trong nganh hoa) de hnh dung. Do on v thng s dung la mg/l, n v nay c dung pho cap.

Tien tnh toan: oi vi ngi lam cong tac xet nghiem, cong thc cang dedang, de nh cang giam thi gian tnh toan, cang tranh c nhng nham lan cothe xay ra.T hai ly do tren, viec chon nong o dung dch chuan c tien hanh nh motthong le sao cho: 1 lt dung dch nh phan luon luon tng ng vi 1g chat cannh lng. ieu nay cung co ngha 1ml dung dch chuan se tng ng vi 1mgchat can nh lng. Ro rang viec pha che dung dch chuan khong phu thuoc vaoban chat chuan ma tuy thuoc vao khoi lng ng lng (KLL) chat canchuan.

Th du phan ngTh du phan ngTh du phan ngTh du phan ngKLLKLLKLLKLLChat can chuanChat can chuanChat can chuanChat can chuan

Dung dchDung dchDung dchDung dchchuanchuanchuanchuan

Nong o dungNong o dungNong o dungNong o dungdch chuandch chuandch chuandch chuan

nh lng amonias KLLNH3 = 17 Acid N/17nh lng nitrogen dangamonia

KLLN-NH3 = 14 Acid N/14

nh lng o kiem dangCaCO3

KLLCaCO3 = 50 Acid N/50

nh lng carbondioxide KLLCO2 = 44 Kiem N/44

nh lng o acid dangCaCO3

KLLCaCO3 = 50 Kiem N/50

nh lng clorua KLLCl = 35,45 AgNO3 N/35,45nh lng NaCl KLLNaCl = 58,4 AgNO3 N/58,44nh lng oxy hoa KLLO2 = 8 Kh N/8

Sau cung cong thc tnh toan ham lng chat can nh lng trong 1 lt maucung tr nen n gian va de nh

Nong o/ham lng chat khao sat (mg/l) =mlmau

chuanmldungdich (1)

Mot vai trng hp nh nh phan oxi hoa tan vi the tch mau an nh trc,nong o dung dch chuan se c hieu chnh vi muc ch toi gian viec tnhtoan. Luc o 1ml dung dch chuan khi dung se tng ng vi 1mg/l oxy.


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2. Chuan b dung dch chuan2. Chuan b dung dch chuan2. Chuan b dung dch chuan2. Chuan b dung dch chuan

Khong phai xac nh lai nong o dung dch chuan sau khi pha che, hoa chatchuan phai co o tinh khiet cao va viec can cac loai hoa chat can can than,ung theo khoi lng tnh toan. Sau khi rot vao cac bnh nh mc co the tch

rieng biet, viec ong o pha che oi hoi mc o chnh xac cao. Thc te nhieutrng hp khong co so lieu ve o tinh khiet hoac kho o lng chnh xac vhoa chat de bay hi, hut am, bien chat nhanh trong khong kh. Dung dch saukhi pha xong phai nh lng lai vi mot dung dch chuan c s ma nong oa biet ro va am bao.

3. nh chuan mot dung dch vi mot dung dch c3. nh chuan mot dung dch vi mot dung dch c3. nh chuan mot dung dch vi mot dung dch c3. nh chuan mot dung dch vi mot dung dch chuan c shuan c shuan c shuan c s3.1 Pha che va xac nh lai nong o dung dch naoh n/503.1 Pha che va xac nh lai nong o dung dch naoh n/503.1 Pha che va xac nh lai nong o dung dch naoh n/503.1 Pha che va xac nh lai nong o dung dch naoh n/50

Dung dch NaOH thng c s dung trong phep nh phan o acid didang CaCO3 co phan t lng M=100, ng lng gam = 50. Do o nong o yeucau la N/50. Tuy nhien NaOH thng mai thng dang vien kho can chnh xac,o hut am cao, de bien chat do CO2 trong khong kh. V the dung dch NaOHN/50 thng c pha loang t dung dch chuan co nong o NaOH 1N e co ochnh xac cao.Dung dch c s la H2SO4 N/10

3.1.1. Thiet b va dung cu3.1.1. Thiet b va dung cu3.1.1. Thiet b va dung cu3.1.1. Thiet b va dung cuCan ky thuat sai so 0.01gBecher 500ml

Bnh nh mc 1000 mlBuretErlen 125ml

3.1.2. Hoa chat3.1.2. Hoa chat3.1.2. Hoa chat3.1.2. Hoa chatNaOH tinh khiet dang vienDung dch chuan c s H2SO4 N/10

3.1.3. Thc hanh3.1.3. Thc hanh3.1.3. Thc hanh3.1.3. Thc hanha.Tna.Tna.Tna.Tnh s khih s khih s khih s khi

NaOH tinh khiet co phan t gam M=40 trung hoa 1,008g H+

, so nglng gam =1e pha che 01 lt dung dch NaOH 1N, khoi lng NaOH tnh c laM/1=40/1=40ge loai bo cac yeu to co the lam giam nong o thc te, he so an toan c tang5%Khoi lng NaOH can thiet : 401,05 =42g


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b. Cach lamb. Cach lamb. Cach lamb. Cach lamDung becher can 42g NaOH vien bang can ky thuatHoa tan lng NaOH trong 500ml nc cat, rot vao bnh nh mc 1000ml.

Tran sach becher nhieu lan vi nc cat. Nhap chung nc ra vao bnh nhmc.

Them nc cat cho u 1000mlDung pipet hut 5ml dung dch tren ra erlen nh phan bang dung dch

chuan H2SO4 N/10. Ch th mau phenolphathalein oi t hong nhat sang mat mau.Nong o NaOH pha che theo cong thc:

N1V1=N2V2 (2)Trong o

N1: Nong o dung dch acid chuan c s N/10V1: The tch dung dch H2SO4 N/10 a dung (ml)N2: Nong o dung dch NaOH pha cheV2: The tch dung dch NaOH trch ra e nh phan (ml)Ket qua tnh c thng ln hn nong o mong muon. Ap dung cong thc (2)

tnh lng nc can e pha loang dung dch NaOH tren thanh 1000ml dung dchNaOH 1NT dung dch NaOH 1N va co, pha che 1000ml dung dch NaOH N/50

3.2. Pha che v3.2. Pha che v3.2. Pha che v3.2. Pha che va xac nh lai nong o dung dcha xac nh lai nong o dung dcha xac nh lai nong o dung dcha xac nh lai nong o dung dch HHHH2222SOSOSOSO4444 NNNN/50/50/50/50Dung dch acid sulfuric thng c s dung trong phng phap nh phan

o kiem di dang CaCO3, do o nong o yeu cau la N/50. ac tnh cua acidsulfuric am ac la de hut am, kho o lng va de gay phong, do o dung dch

H2SO4 N/50 thng c pha loang t dung dch H2SO4 1N lu tr. Dung dchchuan la NaOH 1N va NaOH n/50 a pha loang trong phan tren.

3.2.1. Thiet b va dung cu3.2.1. Thiet b va dung cu3.2.1. Thiet b va dung cu3.2.1. Thiet b va dung cuXem lai phan 2

3.2.2. Hoa ch3.2.2. Hoa ch3.2.2. Hoa ch3.2.2. Hoa chatatatatAcid sulfuric P-A, o tinh khiet 96-98%. Khoi lng rieng d=1.84-1.86g/cm3.Dung dch NaOH 1N

3.2.3. Thc hanh3.2.3. Thc hanh3.2.3. Thc hanh3.2.3. Thc hanha. Tnh s khia. Tnh s khia. Tnh s khia. Tnh s khi

Ap dung cong thc tnh gan ung :V=100M N/b p dTrong o:V: The tch acid sulfuric am ac tnh toan (ml)M: Phan t gam acid sulfuric (g)N: Nong o muon pha


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b: Tr so ng lngp: o tinh khiet (%)d: Khoi lng rieng (g/cm3)Tng t nh tren he so an toan c tang them 2%.The tch acid sulfuric am ac can thiet: V(ml)=v1,02

b. Cach lamb. Cach lamb. Cach lamb. Cach lamDung pipet va qua bop cao su hut can than V(ml) acid sulfuric am ac va

500ml nc cat nh san trong bnh nh mc 1000ml.Dung bnh xt ra sach acid sulfuric con ong trong pipet, rot tat ca nc

ra nhap chungThem nc cat cho u 1000ml

Dung pipet trch dung dch tren ra erlen. nh phan bang dung dch NaOH1N a pha che trong giai oan tren. Ch th mau phenolphthalein chuyen t khongmau sang mau hong nhat ben. Nong o dung dch H2SO4 c tnh t cong thc(2).

Pha loang dung dch tren thanh 1000ml H2SO4Vi dung dch H2SO4 1N va co, pha che 1000ml H2SO4 N/50

3.3.3.3.3.3.3.3. Dung dch chuan FeDung dch chuan FeDung dch chuan FeDung dch chuan Fe3333.3.1.3.1.3.1.3.1. Dung dch lu tr sat. Dung dch lu tr sat. Dung dch lu tr sat. Dung dch lu tr sat

o 20ml H2SO4 am ac vao 50ml nc cat va them vao 1,404Fe(NH4)2(SO4)2.6H2O. Sau khi dung dch ong nhat, them tng giot KMnO4 choen khi xuat hien mau hong nhat khong oi. Pha thanh 1000ml vi nc cat

(1,00ml = 200g Fe).3333.3.2. Dung dch chuan :.3.2. Dung dch chuan :.3.2. Dung dch chuan :.3.2. Dung dch chuan : chuan b moi khi s dung.Lay 50ml dung dch lu tr sat cho vao bnh nh mc 1000ml, them nc

cat ti vach nh mc (1,00ml = 10,00g Fe).

3.4.3.4.3.4.3.4. Dung dch chuanDung dch chuanDung dch chuanDung dch chuan NNNN----NONONONO3333 : (1ml = 2: (1ml = 2: (1ml = 2: (1ml = 2 g Ng Ng Ng N----NONONONO3333))))3.4.1. Dung dch N3.4.1. Dung dch N3.4.1. Dung dch N3.4.1. Dung dch N----NONONONO3333 lu tr: (1ml = 2lu tr: (1ml = 2lu tr: (1ml = 2lu tr: (1ml = 2 g Ng Ng Ng N----NONONONO3333))))Hoa tan 0,7218g Anhydrous Potassium Nitrate KNO3 + nc cat = 1 lt.3.4.2. Dung dch N3.4.2. Dung dch N3.4.2. Dung dch N3.4.2. Dung dch N----NONONONO3333 chuan: (1ml = 0,002mg = 2chuan: (1ml = 0,002mg = 2chuan: (1ml = 0,002mg = 2chuan: (1ml = 0,002mg = 2 g Ng Ng Ng N----NONONONO3333).).).).

Pha loang 10ml dung dch lu tr thanh 500ml e co 1ml dung dch chuan

= 2 g N-NO3.3.5. D3.5. D3.5. D3.5. Dung dch chuanung dch chuanung dch chuanung dch chuan NNNN----NHNHNHNH3333(1ml= 10(1ml= 10(1ml= 10(1ml= 10 g Ng Ng Ng N----NHNHNHNH3333))))3.5.1. Dung dch lu tr NH3.5.1. Dung dch lu tr NH3.5.1. Dung dch lu tr NH3.5.1. Dung dch lu tr NH3333 : ( 1ml=1mg N= 1000: ( 1ml=1mg N= 1000: ( 1ml=1mg N= 1000: ( 1ml=1mg N= 1000 g Ng Ng Ng N----NHNHNHNH3333))))Hoa tan 3,819g NH4Cl( a say kho 100oC), them nc cat cho u mot lt (1ml=1mgN= 1,22 mg NH3)


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3.5.2. Dung dch chuan N3.5.2. Dung dch chuan N3.5.2. Dung dch chuan N3.5.2. Dung dch chuan N----NHNHNHNH3333: (1ml = 10: (1ml = 10: (1ml = 10: (1ml = 10 g Ng Ng Ng N----NHNHNHNH3333))))Pha loang 10ml dung dch lu tr vi nc cat cho u mot lt (1ml=0,010

mgN =0.0122mg NH3)3.6. Dung dch photphate chuan3.6. Dung dch photphate chuan3.6. Dung dch photphate chuan3.6. Dung dch photphate chuan3.6.1.3.6.1.3.6.1.3.6.1. Dung dch lu trDung dch lu trDung dch lu trDung dch lu tr

Hoa tan 219,5 mg KH2PO4 khan (say kho 105o C mot gi) trong nc catva nh mc thanh 1000 ml (1,00 ml=50,0 g P-PO4)3.6.2. Dung d3.6.2. Dung d3.6.2. Dung d3.6.2. Dung dch chuanch chuanch chuanch chuan

Dung 50 ml dung dch chuan pha loang thanh 1000 ml. Dung dch nay conong o 1,00 ml =2,5 g p-PO4.3.7. D3.7. D3.7. D3.7. Dung dch sulfate chuanung dch sulfate chuanung dch sulfate chuanung dch sulfate chuan: (: (: (: (1,00 ml= 1001,00 ml= 1001,00 ml= 1001,00 ml= 100 g SOg SOg SOg SO44442222----))))

Lay chnh xac 10,4 ml H2SO4 0.0200N chuan + nc cat = 100mlhoac147,9 mg NaSO4 khan +nc cat pha thanh 1000 ml.


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-14-

Danh sach tam pDanh sach tam pDanh sach tam pDanh sach tam phan bo cac bai than bo cac bai than bo cac bai than bo cac bai thc hanh Hoa moi trnghc hanh Hoa moi trnghc hanh Hoa moi trnghc hanh Hoa moi trng

Thi lng 60 tiThi lng 60 tiThi lng 60 tiThi lng 60 tietetetetBuoiBuoiBuoiBuoi NhomNhomNhomNhom Ten baiTen baiTen baiTen bai1,2 08 nhom Ly thuyet ve cac thong so vat ly va phan

tch bang pp the tch.Ly thuyet ve cac thong so trac quangLy thuyet ve cac thong so sinh hoa

3,4(4 nhom

lam 1 bai)

N1,N2,N3,N4 Phan tch cac thong so vat ly (pH, EC, oman, o uc, o mau, chat ran)

N5,N6,N7,N8Phan tch cac thong so the tch(o acid, o kiem)

N1,N2,N3,N4 Phan tch cac thong so the tch

N5,N6,N7,N8 Phan tch cac thong so vat ly5,6,7,8(2 nhom

lam 1 baiva hoanoi chonhau)

N1,N2 o cng tong va o cng CanxiN3, N4 PO43- (hoac tong P), Cl-

N5, N6 Fe, NO2-

N7, N8 BOD,COD,DO

9,10 On tap - Thi


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-15-

pH, EC,pH, EC,pH, EC,pH, EC, O MANO MANO MANO MAN

pHpHpHpH

1. Y ngha moi trng1. Y ngha moi trng1. Y ngha moi trng1. Y ngha moi trng

pH la mot thuat ng ch o acid hay baz cua mot dung dch, pH anh hng encac qua trnh sinh hoc trong nc va co anh hng en s an mon, hoa tan cacvat lieu. Trong ky thuat moi trng, pH c quan tam trong cac lnh vc nh quatrnh keo tu, qua trnh lam mem nc, qua trnh kh trung, on nh nc

Trong x ly nc thai bang phng phap sinh hoc, ch tieu pH c duy tr tronggii han toi u e sinh vat phat trien, thng 6.5-7.5

H2O H+ + OH-

pH = -lg[H+]pH + pOH = 14

2. Thc hanh2. Thc hanh2. Thc hanh2. Thc hanh

Trong phan nay sinh vien se thc tap s dung may o pH

- Lac eu mau trc khi o ra coc 100ml e o- Ra sach ien cc bang bnh tia- Bat may, nhung ien cc vao mau can o- i cho gia tr pH tren may on nh oc ket qua- Ra sach ien cc bang nc cat, ngam ien cc vao dd bao quan ien cc.

EC, o manEC, o manEC, o manEC, o man

Gao vien hng dan sinh vien s dung may o


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CHAT RANCHAT RANCHAT RANCHAT RAN

1. Gii thieu chung1. Gii thieu chung1. Gii thieu chung1. Gii thieu chung1.1. Y ngha moi trng1.1. Y ngha moi trng1.1. Y ngha moi trng1.1. Y ngha moi trngChat ran trong nc bao gom chat ran ton tai dang l lng va dang hoa tan.

Trong nc co ham lng chat ran cao gay cam quan khong tot va cac benhng ruot cho con ngi.1.2 Cac nh ngha1.2 Cac nh ngha1.2 Cac nh ngha1.2 Cac nh nghaChat ran tong cong (TS)(TS)(TS)(TS) = Chat ran l lng (SS)(SS)(SS)(SS) + Chat ran hoa tan (TDS)(TDS)(TDS)(TDS)

Chat ran on nh (thanh phan la cac chat vo c): la phan con lai cua chat ran tongcong sau khi ot 550OC

Chat ran khong on nh hay con goi la chat ran bay hi (VSSVSSVSSVSS ---- thanh phan la cacchat hu c): la lng chat ran tong cong mat i sau khi ot 550 OC

2. Thc hanh2. Thc hanh2. Thc hanh2. Thc hanh2.12.12.12.1 Xac nh cXac nh cXac nh cXac nh chat ran tong cong (TS)hat ran tong cong (TS)hat ran tong cong (TS)hat ran tong cong (TS)- Chuan b coc s asay kho 100oC trong 1h, can coc xac nh khoi lng cocban au mo (mg)- Chon the tch mau sao cho lng can nam trong khoang 2,5-200mg, lac eumau trc khi s dung- Cho mau vao coc say 100oC e lam bay hi nc- e nguoi trong bnh hut am en nhiet o phong- Can xac nh khoi lng m

1(mg)

CCCChat ran tong conghat ran tong conghat ran tong conghat ran tong cong(mg/l) = (m(mg/l) = (m(mg/l) = (m(mg/l) = (m1111 mmmmoooo)x)x)x)x1000/V1000/V1000/V1000/Vmaumaumaumau(ml)(ml)(ml)(ml)

2.2 Xac nh cXac nh cXac nh cXac nh chat ran bay hi (VSShat ran bay hi (VSShat ran bay hi (VSShat ran bay hi (VSS Volatile Suspended Solid)Volatile Suspended Solid)Volatile Suspended Solid)Volatile Suspended Solid)- Tiep tuc ly coc tren em nung 550OC- e nguoi trong bnh hut am en nhiet o phong- Can xac nh khoi lng m2 (mg)

CCCChat ran bay hi (mg/l) = (mhat ran bay hi (mg/l) = (mhat ran bay hi (mg/l) = (mhat ran bay hi (mg/l) = (m1111 mmmm2222)x)x)x)x1000/V1000/V1000/V1000/Vmaumaumaumau(ml)(ml)(ml)(ml)

2.32.32.32.3 Xac nh cXac nh cXac nh cXac nh chat ran l lng (SS)hat ran l lng (SS)hat ran l lng (SS)hat ran l lng (SS) bang phng phap khoi lngbang phng phap khoi lngbang phng phap khoi lngbang phng phap khoi lng- Chuan b giay loc si thuy tinh asay kho 100oC trong 1h, can giay loc xacnh khoi lng ban au m3 (mg)- Loc mot the tch mau phu hp qua giay loc (mau a tron eu trc khi loc)- Say giay loc 100oC e lam bay hi nc- e nguoi trong bnh hut am en nhiet o phong


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- Can xac nh khoi lng m4 (mg)

CCCChat ranhat ranhat ranhat ran l lngl lngl lngl lng (mg/l) = (m(mg/l) = (m(mg/l) = (m(mg/l) = (m4444 mmmm3333)x1000/Vmau)x1000/Vmau)x1000/Vmau)x1000/Vmau(ml)(ml)(ml)(ml)

2.2.2.2.4444 Xac nh cXac nh cXac nh cXac nh chat ran l lng (SS)hat ran l lng (SS)hat ran l lng (SS)hat ran l lng (SS) bang phng phap o quangbang phng phap o quangbang phng phap o quangbang phng phap o quang

Lac eu mau trong bnh, lay 50ml mau vao coc 100mlBat may, vao ma chng trnh 636363630000----EnterEnterEnterEnterChnh bc song ve 888811110nm0nm0nm0nmCho nc cat vao Curet en vach trang, nhan Zero cho man hnh xuat hien0.SUSP.SOLIDSCho mau vao Curvet, bam read oc gia tr o.

2.5 Xa2.5 Xa2.5 Xa2.5 Xac nh chat ran hoa tan (TDS)c nh chat ran hoa tan (TDS)c nh chat ran hoa tan (TDS)c nh chat ran hoa tan (TDS)Gao vien hng dan sinh vien s dung may o

2.6 M2.6 M2.6 M2.6 Mt s ch s khc

SVI: ch s lng ca bn

=SS

VSVI

1000

Trong :SS: cht rn l lng (mg/l)

V: th tch lp bn lng sau 30pht trong ngImhoff 1000ml (l)

SVI < 100: bn lng tt ng ImhoffSVI >100: bn ni b mt nhiu100< SVI < 200: bn ni t


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-18-

O UCO UCO UCO UC

1. Gii thieu chung1. Gii thieu chung1. Gii thieu chung1. Gii thieu chung1.1. Y ngha moi trng1.1. Y ngha moi trng1.1. Y ngha moi trng1.1. Y ngha moi trngo uc cua nc bat nguon t s hien hu cua vo so vat the li ti trang thai

huyen phu nh at set, vat chat hu c va vo c, vi sinh vat gom cac loai phieusinh ong vat.1.2. Nguyen tac1.2. Nguyen tac1.2. Nguyen tac1.2. Nguyen tacNguyen tac c ban cua phng phap nay da tren s hap thu anh sang cua caccan l lng co trong dung dch.1.3. Cac tr ngai1.3. Cac tr ngai1.3. Cac tr ngai1.3. Cac tr ngaiCan ln co kha nang lang nhanh, cuvete ban, co bot kh trong mau, o mau thatcua mau la nhng nguyen nhan anh hng ti ket qua o uc.

A) XAC NH O UC BANG PP DNG NG CHUANA) XAC NH O UC BANG PP DNG NG CHUANA) XAC NH O UC BANG PP DNG NG CHUANA) XAC NH O UC BANG PP DNG NG CHUAN (ko lam phan nay)2. Dung cu, thiet b va hoa chat2. Dung cu, thiet b va hoa chat2. Dung cu, thiet b va hoa chat2. Dung cu, thiet b va hoa chat2.1. Dung cu va thiet b :2.1. Dung cu va thiet b :2.1. Dung cu va thiet b :2.1. Dung cu va thiet b :May Spectrophotometer.Pipet 5ml, 25ml.2.2. Hoa chat :2.2. Hoa chat :2.2. Hoa chat :2.2. Hoa chat :

- Dung dch lu tr (s dung trong mot thang)+ Dung dch 1 : hoa tan 1,000g hydrazine sulfate (NH2.NH2.H2SO4) trong

100ml nc cat.+Dung dch 2 : hoa tan 10,00 hexamethylenetetramine (C6H12N4) trong

100ml nc cat.+ Hoa trong 5,0ml dung dch 1 va 5,0 ml dung dch 2. Pha loang thanh100ml vi nc cat, sau o e yen 24 gi nhiet o 253oC. Dung dch nay coo uc la 400 FTU. Lac eu khi s dung.

- Nc dung pha loang khong mau.3. Thc hanh3. Thc hanh3. Thc hanh3. Thc hanh

3.1. Lap ng chuan :3.1. Lap ng chuan :3.1. Lap ng chuan :3.1. Lap ng chuan :- Pha che dung dch chuan : pha loang t dung dch chuan e co o uc

chuan theo bang sau :

STTSTTSTTSTT 0000 1111 2222 3333 4444 5555 6666 7777 8888Vdung dch chuan (ml) 0 2 4 6 8 10 12 14 16Vnc cat (ml) 100 98 96 94 92 90 88 86 84o uc (FTU) 0 8 16 24 32 40 48 56 64


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-19-

- o o hap thu cua cac dung dch chuan tren may spectrophotometer bc song 450nm.

3.2. Lac that ky bnh ng mau, o o hap thu cua mau tren mayspectrophotometer bc song 450nm.

4. Cach tnh4. Cach tnh4. Cach tnh4. Cach tnhT o mau va o hap thu cua dung dch chuan, ve gian o A = f(C), s

dung phng phap bnh phng cc tieu e lap phng trnh y = ax + b. T gia tro hap thu Am cua mau, tnh nong o Cm. Neu tr so Am cua mau vt qua cac trso cua dung dch chuan, phai pha loang mau en nong o thch hp.

5. Cau hoi5. Cau hoi5. Cau hoi5. Cau hoi1.1.1.1. Nguyen nhan tao o uc cho :Nguyen nhan tao o uc cho :Nguyen nhan tao o uc cho :Nguyen nhan tao o uc cho :

o Dong song.o Dong song b o nhiem.o Nc thai sinh hoat.

2. Co s lien quan nao gia cac n2. Co s lien quan nao gia cac n2. Co s lien quan nao gia cac n2. Co s lien quan nao gia cac n v o o uc : mgSiOv o o uc : mgSiOv o o uc : mgSiOv o o uc : mgSiO2222/l, FTU, NTU?/l, FTU, NTU?/l, FTU, NTU?/l, FTU, NTU?

B) XAC NH O UC BANG CHNG TRNH CAI SAN TREN MAYB) XAC NH O UC BANG CHNG TRNH CAI SAN TREN MAYB) XAC NH O UC BANG CHNG TRNH CAI SAN TREN MAYB) XAC NH O UC BANG CHNG TRNH CAI SAN TREN MAY

Lac eu mau trong bnh, lay 50ml mau vao coc 100mlBat may, vao ma chng trnh 750750750750----EnterEnterEnterEnterChnh bc song ve 860nm860nm860nm860nmCho nc cat vao Curet en vach trang, nhan Zero cho man hnh xuat hien

0.FAUTURBIDITYCho mau vao Curvet, bam read oc gia tr o.


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-20-

O MAUO MAUO MAUO MAU1. Gii thieu chung1. Gii thieu chung1. Gii thieu chung1. Gii thieu chung1.1. Y ngha moi trng1.1. Y ngha moi trng1.1. Y ngha moi trng1.1. Y ngha moi trngMau cua nc thien nhien do mun, phieu sinh vat, cac san pham t s phan huychat hu c tao ra. Tuy nhien mot so ion kim loai hay nc thai cong nghiep cung

la nguyen nhan gay cho nc co mau. Theo thoi quen chung ta ngh mau cuanc la mau quan sat c ngay sau khi lay mau. Thc ra ay ch la mau bieukien gom mot phan t chat cac chat hoa tan va phan con lai do chat huyen phutao thanh. V vay mau bieu kien c xac nh ngay tren mau nguyen thuy makhong can loai bo chat l lng. Ngoai ra con co o mau thc cua mau. o mauthc c xac nh tren mau a qua ly tam e loai bo cac hat l lng. Khong nenloc e loai bo cac hat l lng trong nc v cac cau t mau co the b hap phu trengiay loc.1.2.1.2.1.2.1.2. Nguyen tacNguyen tacNguyen tacNguyen tacNguyen tac c ban cua phng phap nay da tren s hap thu anh sang cua cachp chat mau co trong dung dch.1.3. Cac tr ngai1.3. Cac tr ngai1.3. Cac tr ngai1.3. Cac tr ngaio uc anh hng en o mau thc cua mau. Ngoai ra o mau con tuy thuoc vaopH cua nc, do o trong bang ket qua can ghi ro pH luc xac nh o mau.

2222. Thc hanh. Thc hanh. Thc hanh. Thc hanhBat may, vao ma chng trnh 121212120000----EnterEnterEnterEnterChnh bc song ve 455455455455nmnmnmnmCho nc cat vao Curet en vach trang, nhan Zero cho man hnh xuat hien

0.Units PtCo APHACho mau vao Curvet, bam read oc gia tr o.


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CHLORIDECHLORIDECHLORIDECHLORIDE

1. Gii thieu chung1. Gii thieu chung1. Gii thieu chung1. Gii thieu chung1.1. Y ngha moi trng1.1. Y ngha moi trng1.1. Y ngha moi trng1.1. Y ngha moi trng

Chloride (CT) la ion chnh trong nc thien nhien va nc thai. V man cuachloride thay oi tuy theo ham lng va thanh phan hoa hoc cua nc. Vi maucha 250 mg Cl-/l ngi ta a co the nhan ra v man neu trong nc co cha ionNa+. Tuy nhien, khi mau nc co o cng cao, v man lai kho nhan biet du ncco cha en 1000 mg Cl- /l. Ham lng chloride cao se gay an mon cac ket cauong kim loai. Ve mat nong nghiep, chloride gay anh hng xau en s tangtrng cua cay trong.

1.2. Nguyen tac1.2. Nguyen tac1.2. Nguyen tac1.2. Nguyen tac

Trong moi trng trung hoa hay kiem nhe, potassium chromate (K2CrO4) co thec dung lam chat ch th mau tai iem ket thuc trong phng phap nh phanchloride bang dung dch silver nitrate (AgNO3).Ag+ + Cl- AgCl (Ksp = 3 10-10) (1 )2Ag+ + CrO42- Ag2CrO4 (Ksp = 5 10-12) (2 )

o nauDa vao s khac biet cua tch so tan, khi them dung dch AgNO3 vao mau co honhp Cl- va CrO42-, Ag+ lap tc phan ng vi ion Cl- di dang ket tua trang enkhi hoan toan, sau o phan ng (2) se xay ra cho ket tua o gach de nhan thay.

1.3. Cac tr ngai1.3. Cac tr ngai1.3. Cac tr ngai1.3. Cac tr ngai

Nhng chat thng co trong nc uong hau nh khong anh hng g en viecnh phan. Cac ion bromide, iodide, cyanide c xem nh tng ng vichloride. Rieng sulfide, thiosulfate, sulfit co the can thiep vao phan ng (1) . Tuynhien sulfit de dang b oxy hoa bi nc oxy gia (H2O2) trong moi trng trunghoa. Thiosulfate va sulfide b mat anh hng trong moi trng kiem.Orthophosphat vi ham lng cao > 25 mg/l cung tac dung vi silver nitratenhng ieu nay t xay ra. Ham lng sat tren 10 mg/l se che lap s oi mau tai

iem ket thuc.2. D2. D2. D2. Dung cu, thiet b va hoa chatung cu, thiet b va hoa chatung cu, thiet b va hoa chatung cu, thiet b va hoa chat2.1. D2.1. D2.1. D2.1. Dung cu va thiet bung cu va thiet bung cu va thiet bung cu va thiet b- 02 Becher 100 ml- 03 Erlen 100ml- 02 Pipet 10ml- 01 Buret 10ml


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-22-

2.2. H2.2. H2.2. H2.2. Hoa chatoa chatoa chatoa chatDung dch AgNO3 0,0141N: can 2,395g AgNO3 hoa tan vi nc cat va nh

mc thanh 1 lt.Ch th mau K2CrO4: hoa tan 2,5 g K2CrO4 trong 30 ml nc cat, them tng giot

AgNO3 en khi xuat hien mau o ro. e yen 12 gi, loc, pha loang dung dch qua

loc thanh 50 ml vi nc cat.Dung dch huyen treo Al(OH)3 : hoa tan 125 g AlK(SO4). 12H2o hay

Al(NH4)(SO4)2.12H2O trong 1 lt nc cat, lam am 600C, them t t 55 ml NH4OHam ac, lac eu. i 1 gi ra huyen troc nhieu lan vi nc cat en khi ncra khong con Cl- na ( th bang AgNO3) sau o them nc cat cho u 1 lt.

Ch th mau phenolphthalein.Dung dch NaOH 0,1 N( hoac H2SO4 0,1N) tuy pH mau ban au.Nc oxy gia H2O2 30%.

3. T3. T3. T3. Thc hanhhc hanhhc hanhhc hanhLay 10 ml mau hay mot lng mau thch hp va pha loang thanh 10 ml vi

nc cat.Neu mau co o mau cao, them 3 ml huyen treo khuay ky, lang, loc, ra

giay loc, nc ra nhap chung vao nc qua loc.Neu co sulfide, sulfit hoac thiosulfate, them tng giot NaOH 0,1N cho en

khi oi mau phenolphthalein. Them H2O2 quay eu, sau cung trung hoa viH2SO4 0,1N.

nh phan mau trong khoang pH = 7 10 ( tot nhat la 7 - 8). Neu pH ngoaikhoang nay, tot nhat nen trung hoa trc khi them 3 giot ch th K 2CrO4.

Dung dung dch AgNO3 0.0141N nh phan en khi dung dch t mau vangchuyen sang mau o gach (co the so vi mau trang gom nc cat + ch thK2CrO4). Ghi nhan the tch V1 ml AgNO3 s dung.

Lam mau trang co the tch ong vi the tch mau. Ghi nhan the tch Vo mlAgNO3 s dung.

4.4.4.4. CCCCach tnhach tnhach tnhach tnh(V1 - Vo) 500

Chloride (mg/l) = -----------------------ml mau

NaCl (mg/l) = Chloride (mg/l) 1,65Trong o :

V1 : The tch dd AgNO3 dung nh phan mauVo : The tch dd AgNO3 dung nh phan mau trang


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5555. C. C. C. Cau hoiau hoiau hoiau hoi1. Tai sao phai thc hien mau trang trong phng phap nh phan chloride.2. nh phan chloride bang phng phap Morh c thc hien trong moi

trng trung hoa. Giai thch tai sao?3. Ket qua nh phan chloride se nh the nao khi them mot lng tha

chromate.


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O ACIDO ACIDO ACIDO ACID


o acid bieu th kha nang phong thch proton H+ cua nc. o acid cua maunc phan ln do s hien dien cua cac loai acid yeu nh acid carbonic, acid tanic,acid humic bat nguon t phan ng phan huy chat hu c gay ra, phan khac dos thuy phan cac muoi cua acid manh nh sulfate nhom, sat tao thanh. ac bietkhi b cac acid vo c tham nhap, nc se co pH rat thap.

Nc thien nhien s dung cho cap nc luon duy tr mot the can bang gia cacion bicarbonate, carbonate va kh carbon dioxide hoa tan, do o nc thien nhienthng ong thi mang hai tnh chat oi nhau: tnh acid va tnh kiem. Khi b onhiem bi cac acid vo c hoac cac muoi acid t khu vc ham mo, at phen hoacdo nguon nc thai cong nghiep, pH thap hn 7 kha nhieu.

Trong thc nghiem hai khoang pH chan c s dung e bieu th s khac biettren. Khoang pH th nhat ng vi iem oi mau cua chat ch th methyl cam( t4,2 4,5) anh dau s chuyen bien anh hng cua cac acid vo c manh sang vunganh hng cua carbonic acid. Khoang pH th hai ng vi iem oi mau cua chatch th phenolphtalein ( t 8,2 8,4) chuyen sang vung anh hng cua nhomcarbonate trong dung dch.

1.2. Nguyen ta1.2. Nguyen ta1.2. Nguyen ta1.2. Nguyen tac chnhc chnhc chnhc chnhDung cac dung dch kiem manh e nh phan o acid cua ca acid vo c manhcung nh acid hu c hoac acid yeu.o acid do anh hng cua acid vo c c xac nh bang cach nh phan eniem oi mau cua ch th methyl cam nen c goi la O ACID METHYL ( dungdch t mau o chuyen sang da cam).Qua trnh tiep tuc nh phan sau o e xac nh o acid toan phan c thc hienen iem oi mau cua ch th phenolphthalein, goi la O ACID TONGCONG(dung dch khong mau chuyen sang tm nhat).

1.3. Cac tr ngai1.3. Cac tr ngai1.3. Cac tr ngai1.3. Cac tr ngai

Cac chat kh hoa tan lam anh hng en o acid la CO2, H2S, NH3 co the b mati hoac hoa tan vao mau trong qua trnh lu tr hoac nh phan mau. Co the giamanh hng nay bang cach nh phan nhanh chong, tranh lac manh va tranh emau ni co nhiet o cao hn nhiet o ban au cua mau.


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Khi nh phan mau nc cap, ket qua thng b anh hng bi ham lngchlorine kh trung nc co tnh tay mau. Muon tranh sai so nay, can them vaigiot Na2S2O3 0,1N vao mau e loai bo anh hng cua chlorine. Neu mau co omau va o uc cao, phai xac nh o acid bang phng phap chuan o ien the.

2. Du2. Du2. Du2. Dung cung cung cung cu---- thiet bthiet bthiet bthiet b hoa chathoa chathoa chathoa chat

2.1. Dung cu2.1. Dung cu2.1. Dung cu2.1. Dung cu02 Erlen 150 ml01 Ong ong 100 ml01 Buret 25 hoac 50 ml2.2. Hoa chat2.2. Hoa chat2.2. Hoa chat2.2. Hoa chat

Dung dch sodium hydroxide (NaOH) 0,02 N: pha dung dch NaOH 1N(can40g NaOH vien + nc cat = 1 lt) lay 20 ml dung dch NaOH 1N + nc cat = 1lt. nh phan lai bang dung dch potassium biphthlate 0,02 n ( hoa tan 4,085gKHC8H4O4 a say khop6 trong 2 gi 1200C va lam nguoi trong desicator + nccat = 1 lt)

Ch th phenolphthalein : 500 mg phenolphthalein + 50 ml methanol + nccat = 100 ml

Ch th methyl cam : 50 mg methyl cam + nc cat = 100 ml

3. Thc hanh3. Thc hanh3. Thc hanh3. Thc hanh

Neu mau la nc uong, trc khi nh phan them mot giot Na2S2O3 0,1 Ne loai anh hng cua chlorine.

Dung pH ke o pH cua mau. Neu mau co gia tr pH < 4,5: lay 10 ml mauvao erlen, them 3 giot methyl cam. Dung dung dch NaOH 0,02 N nh phan enkhi dung dch co mau da cam. Ghi nhan the tch V1 ml dung dch NaOH a dunge tnh o acid methyl.

Neu mau co gia tr pH > 4,5: lay 10 ml mau vao erlen them 3 giotphenolphthalein. Dung dung dch NaOH 0,02 N nh phan en khi dung dch vaco mau tm nhat. Ghi nhan the tch V2 ml dung dch NaOH a dung, tnh o acidtong cong.

4. Cach tnh4. Cach tnh4. Cach tnh4. Cach tnh V 1000o acid ( mg CaCO3 / l) = --------------

ml mauVi V : the tch dung dch NaOH dung nh phan : V 1, V2


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5. Cau hoi5. Cau hoi5. Cau hoi5. Cau hoi

1.Mau nc co pH = 7,3 va ham lng HCO3 la 30 mg/ l. Gia s rang anh hngcua chat ran hoa tan tren hoat tnh cua cac ion khong ang ke, nhiet o cua ncla 250C. Tnh ham lng CO2 cua mau nc.

2.Nc cap co ham lng HCO3 la 30 mg/ l va ham lng CO2 la 30 mg/l. TnhpH cua nc nhiet o 250C. Neu ham lng CO2 cua mau giam con 3 mg/ l bisuc kh, pH cua nc luc nay la bao nhieu?


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O KIEMO KIEMO KIEMO KIEM


o kiem bieu th kha nang thu nhan proton H+

cua nc. Nc thien nhien haync t he thong cap nc, o kiem eu do 3 ion chnh tao ra: hydroxide,carbonate va bicarbonate. Trong thc te cac muoi acid yeu nh borate, silicatecung gay anh hng ln en o kiem. Mot vai acid hu c ben vi s oxy hoasinh hoc nh acid humic, dang muoi cua chung co kha nang lam tang o kiem.Trong ieu kien thien nhien thch hp, tao de dang xuat hien va ton tai oi vimot vai nguon nc mat, qua trnh phat trien va tang trng cua tao giai phongmot lng ang ke carbonate va bicarbonate lam cho pH nc tang dan co thelen en 9 10. nhng nguon nc c x ly vi hoa chat co cha nhomcarbonate cung lam gia tang pH.

1.2. Nguyen tac1.2. Nguyen tac1.2. Nguyen tac1.2. Nguyen tac

Tien hanh nh phan o kiem vi ch th phenolphtalein va methyl cam(hoac ch th hon hp bromoresol luc = methyl o) trong tng giai oan va tuytrng hp:

Ch th phenolphtalein se co mau tm nhat trong moi trng co ionhydroxide va ion carbonate, mau tim se tr nen khong mau khi pH < 8,3.

Ch th methyl cam cho mau vang vi bat ky ion kiem nao va tr thanhmau o khi dung dch tr thanh acid. Viec nh phan c xem la hoan tat khidung dch co mau da cam ( pH = 4,5), nam gia mau vang ( moi trng baz) vamau o ( moi trng acid). Do o mau iem ket thuc thng c so sanh vihai ong chuan.

V s oi mau cua methyl cam kho nhan thay, nen ch th hon hpbromocresol luc + methyl o co khoang oi mau ro rang hn cung tr so pH nenthng c s dung rong rai hn.

1.3.1.3.1.3.1.3. Cac tr ngaiCac tr ngaiCac tr ngaiCac tr ngai

Lng chlorine d trong nc uong anh hng en ket qua nh phan lamnhat mau chat ch th. e tranh sai lech, ta cho them vao mau mot vai giotNa2S2O3 0,1 N. Khi mau nc co o mau va o uc cao phai dung phng phapchuan o ien the. Nhng chat ket tua, xa bong, chat dau, chat ran l lng co thephu ien cc thuy tinh lam cho iem cuoi en cham. e khac phuc hien tngnay, co the chui electrode moi khi tien hanh th nghiem. Khong loc, pha loanghay co ac mau.


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2222. Dung cu thiet b va hoa chat. Dung cu thiet b va hoa chat. Dung cu thiet b va hoa chat. Dung cu thiet b va hoa chat2.1. Dung cu va thiet b2.1. Dung cu va thiet b2.1. Dung cu va thiet b2.1. Dung cu va thiet b02 Erlen 150 ml01 Ong ong 100 ml01 Buret 25 hoac 50 ml

2.2.2.2.2.2.2.2. Hoa chatHoa chatHoa chatHoa chatDung dch sulfuric acid (H2SO4) 0,02 N: pha dung dch H2SO4 1N ( 28 ml

H2SO4 amac + nc cat = 1 lt), lay 20 ml dung dch H2SO4 1N + nc cat = 1lt. nh phan lai acid nay bang Na2CO3 0,02N ( hoa tan 1,06g Na2CO3 a say 1050C va lam nguoi trong desicator + nc cat = 1 lt).

Ch th mau phenolphthalein 0,5 %Ch th mau methyl cam 0,5 %Ch th mau hon hp bromocresol luc + methyl o: 20 mg methyl o +

200mg bromocresol + 100 ml ethanol 95%

3.3.3.3. TTTThc hanhhc hanhhc hanhhc hanh

Neu mau co pH > 8,3: lay 10ml mau vao erlen, them 3 giot ch th mauphenolphthalein. nh phan bang dung dch H2SO4 0,02N cho en khi mat mau.Ghi the tch V2 ml H2SO4 0,02N a dung e tnh O KIEM PHENOL(P).

Neu mau co pH < 8,3: lay 10 ml mau vao bnh tam giac, them 3 giot ch thmau methyl cam ( hay 3 giot ch th mau hon hp). nh phan mau bang dungdch H2SO4 cho en khi dung dch co mau da cam (mau gia hai Erlen oi(mau gia hai Erlen oi(mau gia hai Erlen oi(mau gia hai Erlen oi

chng)chng)chng)chng). Neu dung ch th hon hp, tai iem ket thuc dung dch co mau o xam.Ghi the tch V2 ml H2SO4 0,02N a dung e tnh O KIEM METHYL CAM hayO KIEM TONG CONG.

Lam haiLam haiLam haiLam hai ErlenErlenErlenErlen oi chngoi chngoi chngoi chng, cho vao hai Erlen moi Erlen 50 ml mau, Erlenth nhat them 1 ml H2SO4 1N + 1 giot methyl cam. Erlen th hai them 1 mlNaOH 1N + 1 giot methyl cam.

4.4.4.4. Cach tnhCach tnhCach tnhCach tnh

V1 1000o kiem P (mg CaCO3 /l) =ml mau

V 1000o kiem tong cong T ( mg CaCO3 /l) =

ml mau


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Da tren ket qua co the tnh o liem do cac ion khac nhau gay ra theo bang sau:

Ket qua phan nhKet qua phan nhKet qua phan nhKet qua phan nh o kiem do cac cac io kiem do cac cac io kiem do cac cac io kiem do cac cac ion ( mg/lCaCOon ( mg/lCaCOon ( mg/lCaCOon ( mg/lCaCO3333))))OH- CO32- HCO3-

P = 0 0 0 T

P < T/2 0 2P T 2PP = T/2 0 2P 0P > T/2 2P - T 2(T P) 0P = T T 0 0

P o kiem phenolT o kiem tong congOH- (mg/l) = o kiem OH- (mg/lCaCO3) 0,34CO32-(mg/l) = o kiem CO32 (mg/lCaCO3) 0,6

HCO3-

(mg/l) = o kiem HCO32

(mg/lCaCO3) 1,22

5.5.5.5. Cau hoiCau hoiCau hoiCau hoiGia s rang anh hng cua cac muoi hoa tan tren hoat tnh cac ion khong angke. Mot phan nc 250C co pH = 10,3 va ham lng carbonate la 120 mg/l.1. Hay tnh ham lng ion bicarbonate (mg/l).2. Tnh o kiem OH, CO32, HCO3 va o kiem tong cong cua mau tren

(mg/lCaCO3).


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O CNG TONG CONGO CNG TONG CONGO CNG TONG CONGO CNG TONG CONG


o cng c hieu la kha nang tao bot cua nc vi xa bong. Ion calci vamagnes trong nc se ket tua vi xa bong, do o lam giam sc can be mat vapha huy ac tnh tao bot. Nhng ion dng a hoa tr khac cung co the ket tuavi xa bong, nhng thng nhng ion nay di dang phc chat, hoac la chathu c, do o anh hng cua chung trong nc khong ang ke va kho xac nh.Tren thc te, o cng tong cong c xac nh bang tong ham lng calci,magnes va c bieu th bang mg CaCO3/l

1.2. Nguyen tac ( phng phap nh phan bang1.2. Nguyen tac ( phng phap nh phan bang1.2. Nguyen tac ( phng phap nh phan bang1.2. Nguyen tac ( phng phap nh phan bang EDTAEDTAEDTAEDTA))))

Ethylenediaminetetraacetic acid (EDTA) hoac muoi natri dan xuat (Na-EDTA)khi them vao dung dch cha nhng ion kim loai a hoa tr dng, pH 10,0pH 10,0pH 10,0pH 10,0 0,10,10,10,1se tao thanh cac phc chat. oi vi hai ion calci va magnes chu yeu gay o cngtrong nc, neu co mot lng nho ch th mau hu c nh Eriochrome Black T(EBT)(EBT)(EBT)(EBT) hay calmagite c cho vao, dung dch tren se tr nen mau o ru vang.nh phan bang EDTAEDTAEDTAEDTA, phn ng tao phc giua EDTA vi ion calci, magnes selam chuyen mau dung dch t o ru vango ru vango ru vango ru vang sang xanh dngxanh dngxanh dngxanh dng tai iem ket thuc.

1.3. Cac anh hng1.3. Cac anh hng1.3. Cac anh hng1.3. Cac anh hng

Mot vai ion kim loai nang gay tr ngai cho viec nh phan, lam ch th maunhat dan hay khong to rang tai iem ket thuc. Co the khac phuc tr ngai naybang cach them chat che luc nh phan. Muoi Mg-EDTA co tac dung nh motchat phan ng kep va tao phc vi cac kim loai nang, va giai phong Mg vaotrong mau, co the dung thay the cho cac chat che co mui kho chu va oc tnh.Muoi Mg-EDTA ch co tac dung tch cc khi thay the cho cac kim loai nang songkhong lam bien oi o cng tong cong trong mau nc.

Bang 1 hng dan cach s dung chat che tuy thuoc ham lng kim loainang hay lng polyphosphate co trong mau, giup viec xac nh Ca va Mg bang

phng phap EDTA; o cng tong cong se co c qua phng phap tnh.


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Bang 1 : HAM LNG TOI A CAC CHAT GAY NHIEU CAN LOAI BO BICHAT CHEChat gay tr ngai Ham lng toi a chat gay tr ngai(mg/l)

Chat che 1 Chat che 2Nhom

BasiumCadmiumCobaltongSatChMangness (Mn2+)NiekelStrontium

KemPolyphosphate

20

++Tren 20Tren 30Tren 30++Tren 20+

+

20

++0,32052010,3+

20010

Lieu lng tren ch thch hp vi 25 ml mau pha loang thanh 50 ml.Nhng lu y khi nh phan

Viec nh phan ch thc hien nhiet o phong hay gan vi nhiet o phong,tranh s cach biet nhiet qua ln so vi nhiet o moi trng xung quanh. S oimau tr nen cham va ket qua kem chnh xac nh trong trng hp mau c nhphan gan khoang nhiet o ong ac. Chat ch th mau se b phan huy trong ncnong. ac biet pH co the tao ra moi trng dan en tua CaCO3, tuy nhien nh

phan co lau cung co the hoa tan lai ket tua. S thay oi cham tai iem ket thucthng cho ket qua thap hn . Nham giam thieu ket tua CaCO3 tao thanh. Viecnh phan can hoan tat trong vong 5 phut. Ba phng phap sau ay lam giam kettua CaCO3.

Pha loang mau bang nc cat e toi giam lng CaCO 3. Dung mot lngmau qua nho de dan en sai lech khi oc ket qua tren than ong nho giot.

Neu o cng a c biet hay a c xac nh bang phng phap nhphan s bo. Them nhanh EDTA vi khoang 90 % lng can dung hay mot t lethch nghi tuy vao the tch mau can nh phan trc khi chnh pH bang dung dchem.

Acid hoa mau va khuay trong vong 2 phut e uoi CO2 trc khi chnh pHxac nh o kiem sau moi lan them axit.


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2. Dung cu, thiet b va hoa chat2. Dung cu, thiet b va hoa chat2. Dung cu, thiet b va hoa chat2. Dung cu, thiet b va hoa chat2.1. Dung cu va2.1. Dung cu va2.1. Dung cu va2.1. Dung cu va thiet b thiet b thiet b thiet b02Coc 250 ml01 Buret 10 ml01Erlen 100 ml

Ong ong

2.2. Hoa chat2.2. Hoa chat2.2. Hoa chat2.2. Hoa chat2.2.1.Dung dch em2.2.1.Dung dch em2.2.1.Dung dch em2.2.1.Dung dch em

a. Hoa tan 16,9g NH4CL trong 143 ml NH4OH am ac + 1,25g muoi Mg-EDTA + nc cat = 250 ml

b. Neu khong co muoi Mg- EDTA, hoa tan 1,179g muoi Na-EDTA(PA) + 780mg MgSO4.7H2O hoac 644 mg MgCL2. 6H2O trong 50 ml nc cat.Hoa tan 16,9g NH4CL trong 143 ml NH4OH am ac.Tron eu hai dung dch tren va pha loang thanh 250 ml vi nc cat.e at o chnh xac cao can gi ung t le ve phan lng gi cac hoa chat

tren.ng cac dung dch tren trong chai nha deo hay chai thuy tinh trung tnh.Thi han s dung khong qua mot thang. ay nap kn e ngan NH 3 bay hi vaCO2 ngoai khong kh khong xam nhap vao dung dch.

Them vao mau 1- 2 ml dung dch em, neu dung dch mau nh phan chaat ti pH 10,0 0,1 tai iem ket thuc chuan o.

2.2.2.Nhng tac nhan che2.2.2.Nhng tac nhan che2.2.2.Nhng tac nhan che2.2.2.Nhng tac nhan che

Phan ln cac loai nc khong can them tac nhan che. Tuy nhien mot vai maunc cha nhng ion gay nhieu, can them tac nhan che e lam s oi mau taidt iem c ro rang. Sau ay la nhng chat che thch hp.Chat che IMau co tnh acid phai c trung hoa ti khi pH = 6 bang dung dch em hayNaOH 0,1 Ntru7c khi them 200 mg sodium cyanide ( NaCN) di dang tinh the.Them u dung dch em e co pH 10 0,1. ( Chu y: NaCN rat oc. Can than khis dung no. Xa that nhieu nc trc khi o bo dung dch tren e tranh phan ngtoa hi oc hydroxyanide (HCN)).Chat che II

Hoa tan 5g NaS. 9H2O hay 3,7g Na2S. 5H2O trong 100 ml nc cat.Dung dch Na2S de b oxy hoa bi kh tri tao ra ket tua sulfide anh hng enviec xac nh iem chuyen mau chat ch th. Phai bao quan dung dch nay trongchai ay kn bang nut cao su. Khi biet ro co s hien dien cua cac kim loai nang,s dung chat che x ly mau trc khi nh phan ( xem phan nhng lu y khi nhphan)


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2.2.3. C2.2.3. C2.2.3. C2.2.3. Chat ch th mauhat ch th mauhat ch th mauhat ch th maua. Eriochrome Black T : muoi natri dan xuat t 1 ( 1 hyroxy 2 naphthylazo

5 nitro 2 naphthol 4 sulfonic acid), hoa tan 0,5 g ch th tren 100 g 2,2,, 2,, - nitrilotriethanol. Them hai giot cho moi 50 ml mau. Chnh the tchmau nc can thiet.

b. Calmagite: 1 ( 1 hydroxy 4 methyl 2 phenylazo) 2 napthol 4sulfonic acid. Calmagite thch hp cho dung dch long va tao ra s thay oimau tng t nh Eryochrome Black T. vi iem ket thuc ro rang hn.Hoa tan 0,10 g Calmagite trong 100ml nc cat. Dung 1ml cho moi 50 mlmau nh phan. Chnh the tch neu can thiet.

c. Chat ch th I va II co the dung di dang tinh the kho. Khong nen dungchat ch th qua nhieu. Chan b hon hp kho cua chat ch th di muoi tinhthiet.

d. Neu tai iem ket thuc chuan o, s thay oi mau cua ch th khong ro rangtrong trng hp nay can phai them tac nhan che. Neu cho chat che NaCNvao mau ma iem oi mau van khong ro rang, nguyen nhan co the do chatch th mau b h.

2.2.4. Dung dch chuan EDTA 0,01 M2.2.4. Dung dch chuan EDTA 0,01 M2.2.4. Dung dch chuan EDTA 0,01 M2.2.4. Dung dch chuan EDTA 0,01 MCan 3,723g EDTA. Hoa tan trong nc cat va pha thanh 1000 ml, chuan o

lai bang dung dch Calcium.Dung dch chuan EDTA phai c ng trong chai thuy tinh trung tnh hay

bnh nha polyethylen.

2.2.5. Dung dch chuan Calcium2.2.5. Dung dch chuan Calcium2.2.5. Dung dch chuan Calcium2.2.5. Dung dch chuan CalciumCan 1g CaCO3 ( dung chat chuan tot nhat hay hoa chat at biet co hamlng cac kim loai nang, o kem va magnesium thap) vao trong mot erlen 500ml. at mot cai phieu tren mieng bnh, moi lan them mot t HCL ( 1+ 1) cho tikhi tat ca CaCO3 tan hoan toan. Them 200 ml nc cat va un soi vai phut e oiCO2 lam lanh va them vai giot ch th methyl o, chnh lai pH en khi co maucam bang NH4OH 3N hay HCL ( 1 + 1) chuyen qua bnh nh mc va pha thanhmot lit1 vi nc cat : 1 ml = 1 mg CaCO3.

2.2.6. Dung dch sodium hydroxide :2.2.6. Dung dch sodium hydroxide :2.2.6. Dung dch sodium hydroxide :2.2.6. Dung dch sodium hydroxide : NaOH 0,1 N.

3.3.3.3. Trnh t th nghiemTrnh t th nghiemTrnh t th nghiemTrnh t th nghiemLay mot the tch mau sao cho lng EDTA chuan o khong qua 15 ml,

hoan thanh viec nh phan trong vong 5 phut tnh t thi iem cho dung dchem. Neu lng EDTA ln hn 15ml th phai pha loang mau.


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Lay 25ml mau, them 1 ti 2 ml dung dch em, thng dung 1 ml u e atpH 10 0,1, them chat che neu s thay oi mau tai iem ket thuc chuan okhong ro rang. Sau khi them chat che nhng mau the hien van khong ro rang.Chat ch th co the a b hong.

Them chat ch th mau (lng nho bang 1/5 hat gao). Chuan o t t bang

dung dch EDTA cho en luc co mau xanh da tri lai iem ket thuc . Neu the tchmau co u va khong co chat gay can tr th tr so nh phan se tang khi s dung 1lng mau nhieu hn c mieu ta trong phan c di ay.

Mau co o cng thap: nc sau khi qua trao oi ion, cac loai nc memkhac va cac loai nc thien nhien co o cng thap ( t hn 50 mg/l) can lay 1 thetch ln hn (100 1000 ml) e nh phan va them vao mot lng dung dch em.Chat che. Chat ch th mau theo t le tng ng. Chuan o bang ong nho giotnh phan nho nhat, lam them mau th khong: dung nc cat 2 lan nc qua cottrao oi ion bang the tch mau .Lng dung dch em. Chat che. Chat ch th mautng t nh mau. Lay the tch EDTA nh phan cua mau tr i the tch dungnh phan cho mau th khong.

4. Cach tnh4. Cach tnh4. Cach tnh4. Cach tnh( A B 1000)

o cng ( EDTA) mg CaCO3 /l = ............ml mau

Trong o:A ml EDTA tham gia phan ng trong mauB mg CaCO3 tng ng 1 ml EDTA nh phan.

5. Cau ho5. Cau ho5. Cau ho5. Cau hoiiii1. Nguyen nhan gay ra o cng cua nc?2.Mau nc c phan tch co cac ket qua nh sau:

Na+ = 20mg/l Cl- = 40 mg/lK+ = 30 mg/l HCO3- = 40 mg/lCa2+ = 15 mg/l CO32- = 67 mg/lMg2+ = 10 mg/l SO42 = 5 mg/lSr2+ = 2 mg/l NO3- = 10 mg/lTnh o cng tong cong, o cng carbonate, bicarbonate cua mau

nc; ( n v mgCaCO3/l)


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O CNG CALCIO CNG CALCIO CNG CALCIO CNG CALCI

1. G1. G1. G1. Gii thieu chungii thieu chungii thieu chungii thieu chungCalci la mot nguyen to thng gap trong nc thien nhien v chay qua

nhng vung co nhieu a voi, thach cao, dolomit Tuy theo nguon goc va cach

x ly ma ham lng calci trong nc co t 0 en vai tram mg/l. Ch vi motlng nho calcicacbonate cung co the tao nen mot mang cng bam vao mat trongcac ong dan theo thi gian tch tu, bao ve kim loai chong lai s an mon. Matkhac, lp mang nay lai la mot tai hai ln cho nhng thiet b s dung nhiet ocao nh noi hi Phng phap lam mem nc bang hoa chat hoac nha trao oiion thng c ap dung e kh bt calci ti gii han chap nhan c

2. N2. N2. N2. Nguyen tacguyen tacguyen tacguyen tacTrong dung dch co cha calci va magnes, pH12-13, magne se b ket tua didang hydroxy. Chat ch th mau ket hp vi calci cho mau hong. Khi DETA cthem vao dung dch se ket hp vi calci va phan ng xay ra hoan toan. iemket thuc dung dch chuyen mau hong sang tmCAC ANH HNG (XEM PHAN O CNG)

3. D3. D3. D3. Dung cu, thiet b, hoa chatung cu, thiet b, hoa chatung cu, thiet b, hoa chatung cu, thiet b, hoa chat3.1. D3.1. D3.1. D3.1. Duuuung cung cung cung cuErlenPipetBuret

Ong ong3.2. H3.2. H3.2. H3.2. Hoa chatoa chatoa chatoa chatDung dch NaOH 1NCh th mau Murexider: Can 200g murexider + 100g NaCl nghien nho, tron euDung dch EDTA 0.01M: Xem phan o cng

4. T4. T4. T4. Thc hanhhc hanhhc hanhhc hanhe tranh ket tua, viec nh phan can thc hien nhanh chong sau khi nang pH

a. Lay 25ml (hay mot the tch mau pha loang en 25ml) sao cho the tchEDTA dung nh phan khong vt qua 15ml. Neu mau nc co ham lngcalci vt qua 300mg/l nen pha loang hoac trung hoa vi acid roi un soimot phut, lam nguoi trc khi nh phan.

b. Them 2ml dung dch NaOH 1N hoac mot the tch ln hn e nang pH len12-13, lac eu

c. Them 0,1-0,2g ch th mau murexider (lng nho bang 1/5 hat gao), dungdch co mau hong nhat


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d. nh phan bang dung dch EDTA 0,01M, iem ket thuc dung dch co mauo ta. e kiem soat iem ket thuc chuan o, can ghi nhan the tch EDTAa dung, sau o them mot hoac hai giot EDTA e am bao mau cua dungdch khong oi

5. C5. C5. C5. Cachachachach tnhtnhtnhtnhcalci (mg/l) =

mlmau

VMlEDTA 1000

o cng calci (mgCaCO3) =mlmau

VmlEDTA 1000


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SATSATSATSAT

1.Gii thieu chung1.Gii thieu chung1.Gii thieu chung1.Gii thieu chung1.1. Y ngha moi trng1.1. Y ngha moi trng1.1. Y ngha moi trng1.1. Y ngha moi trng

T lau con ngi a nhan biet, uong nc co cha sat se khong gay hai

oi vi sc khoe. Nc mat sau khi loai bo can l lng th ham lng sat t khiat ti 1mg/l. Rieng oi vi nc ngam va nc thai sinh hoat, ham lng sat cothe cao hn rat nhieu. Nhng loai nc nh the khi tiep xuc vi khong kh se trnen uc va co mau vang, nguyen nhan la do sat dang Fe 2+ b oxy hoa thanh Fe3+tao ra nhng chat ket tua di dang keo. nhng ieu kien t nhien va pH thap,toc o cua qua trnh oxy hoa thng xay ra cham va sat trong nc thng ton taidi dang Fe2+. Trong moi trng pH 6, co mat cuacac chat oxy hoa hay do hoat ong cua vi sinh vat. Sat co trong nc la nguyennhan lam cho quan ao b vang sau khi giat, lam o cac o vat bang s va tao racac vet o tren cac o vat han ch. Khi ham lng sat trong nc ln hnmg/l gayra v tanh trong nc va ve mat cam quan khong the chap nhan c. Ngoai ra,can sat bam tren thanh ongdan lau ngay lam thay oi lu lng va tac cac ongdan cua he thong phan phoi nc. Chnh v nhng ly do tren nen tieu chuan atra cho nc s dung trong sinh hoat va an uong phai co ham lng Fe tc < 0,3mg/l. oi vi mot so nganh cong nghiep, tieu chuan cho phep sat co trong ncoi hoi rat cao nh oi vi cong nghe det nhuom th Fe < 0,1 mg/l.

1111.2. Nguyen tac.2. Nguyen tac.2. Nguyen tac.2. Nguyen tac

Sat trong dung dch c kh thanh dang Fe

2+

(tan trong nc) bang cachun soi trong moi trng acid va hydroxylamine, sau o Fe2+ tao phc co mau vi1,10 phenanthroline pH = 3,0 3,3. Moi nguyen t Fe2+ se ket hp vi ba phant cua phenanthroline tao thanh phc chat mau o cam. Cng o mau tuan theonh luat Lambert-Beer va phu thuoc vao pH. Phan ng se at toc o cc ai khipH cua moi trng trong khoang t 2,9 3,5 va s dung mot lng thaphenanthroline. Cac phng trnh phan ng c bieu dien nh sau :Fe(OH)3 + 3H+ Fe 3+ + 3H2O4 Fe 3++ 2NH2OH 4 Fe 2+ + N2O + 4H+ + H2O

N N

3+ Fe2+

FeN-N

N-N N-

N

2+

(mau o cam)


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1.3. Tr ngai1.3. Tr ngai1.3. Tr ngai1.3. Tr ngaiNhng chat oxy hoa manh nh cyanide, nitrite va phosphate

(polyphosphate manh hn orthophosphate), chromium, zine vi ham lng lnhn sat 10 lan, cobalt, copper ln hn 5mg/l va nicken ln hn 2 mg/l eu gayanh hng en ket qua phan tch. Bismuth, cadmium, mercury, molybdate va

silver ket tua vi phenanthroline. Trong qua trnh thc hien th nghiem, bc unsoi vi acid nham chuyen polyphosphate thanh orthophosphate, loai bo anhhng cua nitrite va cyanide. Them mot lng tha phenanthroline e loai bonhng sai so gay ra bi cac chat oxyhoa manh va tao phc vi mot so ion kimloai co trong dung dch. Neu ham lng cac ion kim loai qua cao, can phai sdung phng phap trch ly.

Neu mau co mau hay chat hu c, x ly mau bang cach un soi mau nhieugi vi acid HCl 1:1 trong coc co quai bang silica, s hay platinum. Khi mau can,ot nhe, phan tro con lai c hoa tan bang acid. Neu ham lng chat hu c quacao, bc phan huy se c thc hien trc giai oan trch ly.

Phng phap phenanthroline co the xac nh ham lng sat nho nhat la10g.

2 .2 .2 .2 . Dung cu, thiet b va hoa chatDung cu, thiet b va hoa chatDung cu, thiet b va hoa chatDung cu, thiet b va hoa chat2.1. Dung cu va thiet b2.1. Dung cu va thiet b2.1. Dung cu va thiet b2.1. Dung cu va thiet b2.1.1. Dung cu2.1.1. Dung cu2.1.1. Dung cu2.1.1. Dung cu

Dung cu thuy tinh: nham loai bo sat bam tren thanh dung cu can phai ratat ca dung cu thuy tinh bang acid HCl am ac, trang lai bang nc cat trc khis dung.

+ 02 Erlen 125ml+ 01 Ong ong 50ml+ 06 Bnh nh mc 100ml.+ 02 pipet 2ml, 5ml, 10ml+ 01 pipet 25ml

2.1.2.Thiet b:2.1.2.Thiet b:2.1.2.Thiet b:2.1.2.Thiet b:+ Spectrophometer+Bep ien

2.2. Hoa chat:2.2. Hoa chat:2.2. Hoa chat:2.2. Hoa chat:S dung nhng hoa chat co ham lng sat thap va nc cat khong co sat

e chuan b cac dung dch chuan va tac nhan.


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2.2.1.. Hydrochloric acid (HCl) am ac.2.2.1.. Hydrochloric acid (HCl) am ac.2.2.1.. Hydrochloric acid (HCl) am ac.2.2.1.. Hydrochloric acid (HCl) am ac.2.2.2.2.2.2.2.2.2.2.2.2.Dung dch hydroxylamine:Dung dch hydroxylamine:Dung dch hydroxylamine:Dung dch hydroxylamine:hoa tan 10g NH2OH.HCl trong 100ml nc cat.2.2.3.2.2.3.2.2.3.2.2.3. Dung dch em ammonium acetateDung dch em ammonium acetateDung dch em ammonium acetateDung dch em ammonium acetate (NH(NH(NH(NH3333CCCC2222HHHH3333OOOO2222):):):): hoa tan 250g NH3C2H3O2trong 150ml nc cat, them 700ml acid acetic (CH3COOH) am ac. Lac eu.2.2.4. Dung dch phenanthroline:2.2.4. Dung dch phenanthroline:2.2.4. Dung dch phenanthroline:2.2.4. Dung dch phenanthroline:

Cach 1:Cach 1:Cach 1:Cach 1: hoa tan 100mg 1,10 phenanthroline (C12H8N2.H2O) trong 100mlnc cat, khuay va un ti 80oC. Khong c un soi.

Cach 2:Cach 2:Cach 2:Cach 2: cho 10ml nc cat vao trong coc cha 100mg phenanthrolineC12H8N2.H2O, them 2 giot acid am ac, khuay eu en khi tan hoan toan, phaloang thanh 100ml.

Khong s dung khi dung dch co mau.2.2.5. Dung dch lu tr sat2.2.5. Dung dch lu tr sat2.2.5. Dung dch lu tr sat2.2.5. Dung dch lu tr sat::::

o 20ml H2SO4 am ac vao 50ml nc cat va them vao 1,404gFe(NH4)2(SO4)2.6H2O. Sau khi dung dch ong nhat, them tng giot KMnO4 choen khi xuat hien mau hong nhat khong oi. Pha thanh 1000ml vi nc cat(1,00ml = 200g Fe).2.2.6. Dung dch chuan :2.2.6. Dung dch chuan :2.2.6. Dung dch chuan :2.2.6. Dung dch chuan : chuan b moi khi s dung.

Lay 50ml dung dch lu tr sat cho vao bnh nh mc 1000ml, them nccat ti vach nh mc (1,00ml = 10,00g Fe).

3. Thc hanh3. Thc hanh3. Thc hanh3. Thc hanh3.1. Sat tong cong3.1. Sat tong cong3.1. Sat tong cong3.1. Sat tong cong (Fe(Fe(Fe(Fe tctctctc))))

Mau phai c lac eu trc khi phan tch, lay 50ml mau cho vao erlen.Neu the tch mau co ham lng sat cao hn 200g, s dung mot lng mau t hn

va pha thanh 50ml. Them 2ml HCl am ac va 1ml NH2OH.HCl. Them vai vienbi thuy tinh vao erlen, un soi en khi the tch con khoang 15 20ml (neu mau bcan, cho vao 2ml HCl am ac va 5ml nc cat).

Lam nguoi mau nhiet o phong, chuyen dung dch vao bnh nh mc100ml, them 10ml dung dch em NH3C2H3O2 va 4ml dung dch phenanthroline.Cho nc cat ti vach nh mc va lac eu, sau o e khoang 10 15 phut chocng o mau at cc ai va on nh. o o hap thu tren may spectrophotometer bc song 510nm.

3.2. Sat hoa tan3.2. Sat hoa tan3.2. Sat hoa tan3.2. Sat hoa tan

Ngay sau khi lay mau, loc mau bang giay loc co ng knh 0,45m, ncsau loc c acid hoa vi t le 1ml HCl am ac/100ml mau. Tong ham lng sathoa tan c xac nh nh trong phan 3.1.


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3.3. Sat hai3.3. Sat hai3.3. Sat hai3.3. Sat hai (Fe(Fe(Fe(Fe2+2+2+2+))))Viec xac nh Fe2+ phai thc hien tai v tr lay mau bi v co s thay oi ty

le gia Fe2+ va Fe3+ theo thi gian trong moi trng acid. e xac nh Fe2+, acidhoa mau theo t le 2ml HCl am ac/100ml mau tai thi iem lay mau.

Lay 50ml mau a c acid hoa, them 20ml phenanthroline va 10ml dung

dch em NH4C2H3O2, lac eu. Pha thanh 100ml vi nc cat, i khoang 1015phut, sau o o o hap thu A bc song 510nm.

4.4.4.4. Cach thanh lap ng cong chuanCach thanh lap ng cong chuanCach thanh lap ng cong chuanCach thanh lap ng cong chuanS dung dung dch chuan co nong o 1ml = 101ml = 101ml = 101ml = 10g Fe.g Fe.g Fe.g Fe.Pha loat dung dch chuan sat nh sau :

STTSTTSTTSTT0000 1111 2222 3333 4444 5555

V dd chuan (ml) 0 2 4 6 8 10V nc cat (ml) 50 48 46 44 42 40V HCl am ac (ml) 2V dd NH2OH.HCl (ml) 1V dd em ammonium acetateNH3C2H3O2 (ml)

10

V dd phenanthroline (ml) 4** nh mc 100mlHam lng Cg 0 20 40 60 80 100Nong o C mg/l 0 0,2 0,4 0,6 0,8 1,0o hap thu A (o bang may) bc

song 510nm.

zero ? ? ? ? ?

Chu thchChu thchChu thchChu thch** nh mc thanh 100ml bang nc cat. Lac eu va o o hap thu.Neu mau b uc va co mau, thay v s dung nc cat lam mau chuan trang, sdung chnh mau lam mau chuan trang va x ly mau qua tat ca cac bc nh trongqua trnh thc hien nhng khong cho phenanthroline.

5. T5. T5. T5. Tnh tnh tnh tnh toanoanoanoanSau khi co o hap thu cua mot loat chuan. Ve gian o A = f(C), s dung

phng phap bnh phng cc tieu e lap phng trnh y= ax + b. T tr so o hapthu cua dung dch mau Am suy ra Cm t phng trnh tren. Ket qua bieu dienbang n v mg/l.6.6.6.6. Cau hoiCau hoiCau hoiCau hoi

6.1.6.1.6.1.6.1.Trnh bay nhng trang thai khac nhau cua sat trong nguon nc tnhien, neu ieu kien ton tai cua moi trang thai.

6.2.6.2.6.2.6.2.Neu nhng nguyen nhan chnh gay o nhiem sat trong nguon ncngam.


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NITROGENNITROGENNITROGENNITROGEN NITRITE (NNITRITE (NNITRITE (NNITRITE (N NONONONO2222))))

1. Gii thieu chung1. Gii thieu chung1. Gii thieu chung1. Gii thieu chung1. 1 Y1. 1 Y1. 1 Y1. 1 Y nnnnghaghaghagha mmmmoioioioi ttttrngrngrngrngNitrite la mot giai oan trung gian trong chu trnh am hoa do s phan huy cac

chat am hu c. V co s chuyen hoa gia nong o cac dang khac nhau cuanitrogen nen cac vet nitrite c s dung e anh gia s o nhiem hu c. Trongcac he thong x ly hay he thong phan phoi cung co nitrite do nhng hoat ongcua vi sinh vat. Ngoai ra nitrite con c dung trong nganh cap nc nh motchat chong an mon. Tuy nhien, trong nc uong, nitrite khong c vt qua 0.1mg/l.

1.2 Nguyen1.2 Nguyen1.2 Nguyen1.2 Nguyen ttttacacacacNitrite c xac nh bang phng phap so mau. Mau do phan ng t cac dungdch tham chieu va mau sau khi tac dung vi acid sulfanilic va naphthylamine moi trng pH = 2 2.5 tao thanh hp chat mau o tm cua acid azobelzolnaphthylamine sulfonic nh sau:

HSO3- -NH3 + NaNO2 HSO3- -N=N+Cl- + NaCl + H2O

Phng phap DIAZO thch hp khi xac nh ham lng N-NO2 t lg/25-1

1.3 Cac1.3 Cac1.3 Cac1.3 Cac nhnhnhnh hhhhngngngngChlorine va nitrogen trichloride ton tai trong mau se gay ra tr ngai oi vi

phng phap nay. Anh hng nay se giam thap khi them naphthylaminehydrochloride trc, sau o en acid sulfanilic. Nhng ion tao ket tua lam sailech ket qua nh: Sb, Fe3+, Pb2+, Hg2+, Ag+, khong nen ton tai trong mau. Motlng nho chat ran l lng cung gay can trm co the loc qua giay loc kch thc

m0.45

2 . Dung cu, thiet b va hoa chat2 . Dung cu, thiet b va hoa chat2 . Dung cu, thiet b va hoa chat2 . Dung cu, thiet b va hoa chat2.1. Dung cu va thiet b2.1. Dung cu va thiet b2.1. Dung cu va thiet b2.1. Dung cu va thiet b2.1.12.1.12.1.12.1.1 Dung cuDung cuDung cuDung cuPipet 1ml (1); ong ong 50ml (1); pipet 25ml (1)

Erlen 125ml (9); qua bop cao su (1)Coc ot 100ml (1)SpectrophotometerOng o o truyen suot


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2.1.2 Hoa Chat2.1.2 Hoa Chat2.1.2 Hoa Chat2.1.2 Hoa Chata. Dung dch chuan

Dung dch lu tr NDung dch lu tr NDung dch lu tr NDung dch lu tr N----NONONONO2222: (1ml = 250 g N-NO2): NaNO2 0.05: hoa tan1.232g NaNO2 trong nc cat va nh mc thanh 1000ml.

Dung dch NDung dch NDung dch NDung dch N----NONONONO2222 chuanchuanchuanchuan (1ml = 0.0005mg = 0.5 g N-NO2): Lay 2ml dungdch lu tr + nc cat = 1 lt.

Xac nh lai nong o dung dch NO2- mi pha bang cach pha cac dung dch sau: KMnO4 0.05N: can 1.6g KMnO4 + nc cat = 1 lt. FAS 0.05N: can 19.607g Fe(NH4)2(SO4)2.6H2O + 20ml H2SO4 am ac +

nc cat = 1 lt. Na2C2O4 0.05N: can 3.350g Na2C2O4 the6m nc cat cho u 1 lt (neu

khong dung FAS).

Cho vao bnh thuy tinh co mai 50ml KMnO4 0.05N va 5ml H2SO4 am ac, them50ml dung dch NaNO2 0.05N (hoac Na2C2O4 0.05N) vi dung dch bang cachthem moi lan 10ml dung dch FAS (hoac Na2C2O4) vi dung dch KMnO4 0.05Nen khi dung dch chuyen sang mau hong nhat. Tnh nong o cua dung dch lutr N-NO2 bang cong thc:

F

EDCB

A

7*)]*()*[(

= mg/ml N-NO2B ml dung dch KMnO4 a dungC nguyen chuan o cua dung dch KMnO4 (0.05N)D ml FAS (hoac Na2C2O4) a dungE nguyen chuan o cua dung dch chuan (0.05N)F ml dung dch NaNO2 dung nh phanb. Dung dch EDTA: can 0.5g muoi natri dan xuat t EDTA + nc cat =

100ml

c. Acid sulfanilic + 70ml nc nong e nguoi + 20ml HCl am ac pha loangthanh 100ml vi nc cat.

d. Dung dch Naphthylamine chlohydrate: can 0.6g naphthylaminechlohydrate + 50ml nc cat + 1ml HCl am ac + nc cat = 100ml. Pha dungngay hoac lu gi nhiet o thap.


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e. Dung dch em axetat: can 16.4g CH3COONa hay 27.2g CH3COONa.3H2O+ nc cat = 100ml.

f. Dung dch huyen treo Al(OH)3: can 125g AlK(SO4)2.12H2O hayAl(NH4)(SO4)2.12H2O trong 1000ml nc cat, un nhe en 600C + 55ml NH4OH

am ac. T t lac eu. c 1 gi, ra huyen troc nhieu lan vi nc cat enkhi nc ra khong con Cl- (th bang AgNO3). Sau o them nc cat cho thanh1000ml.

2.22.22.22.2 TrnhTrnhTrnhTrnh tttt tttthhhh nnnnghiemghiemghiemghiema. Neu mau th nhieu chat l lng va mau, them 2ml Al(OH) 3 vao 100ml

mau, e lang vai phut, loc bo lp nc qua loc au tien. (Neu mau trong thkhong phai lam bc nay).

b. Chuan b mau va dung dch tham chieu (ng chuan) theo bang sau:STTSTTSTTSTT 0000 1111 2222 3333 4444 5555 6666

ml dd N-NO2 chuan 0 2.5 5 7.5 10 12.5 0ml nc cat 2.5 22.5 20 17.5 15 10 -ml mau nc - - - - - - 25ml dd EDTA 0.5ml/ongml acid sulfanilic 0.5ml/ong i 10 phutml naphthylamine 0.5ml/ongml dd em axetat 0.5ml/ong i 20 phut

C ( g ) 0 1.25 2.5 3.75 5.0 6.25 -C (mg/l) 0 0.05 0.1 0.15 0.2 0.25 -

Cac dung dch theo ung th t trong bang, sau moi lan them dung dch phan ngch ung thi gian qui nh.c. o o hap thu A bc song nm520= 2.3 Tnh Toan2.3 Tnh Toan2.3 Tnh Toan2.3 Tnh ToanT loat chuan o o hap thu. Ve gian o A = f(C), s dung phng phap bnhphng cc tieu e lap phng trnh y = ax + b.

2.4 Cau Hoi2.4 Cau Hoi2.4 Cau Hoi2.4 Cau Hoia. Phan tch mot mau nc ngam, ket qua ham lng nitrite cao, co the ket

luan g?b. Nitrogen thng ton tai dang nao trong nc mat? Nc giam?


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PHOSPHATEPHOSPHATEPHOSPHATEPHOSPHATE1. Gii thieu chung1. Gii thieu chung1. Gii thieu chung1. Gii thieu chung1.1.Y1.1.Y1.1.Y1.1.Y ngha moi trngngha moi trngngha moi trngngha moi trng

Trong thien nhien phosphate c xem la san pham cua qua trnh lan hoa,thng

gap dang vet oi vi nc thien nhien.Khi ham lng phosphate cao se la motyeu to giup rong reu phat trien manh .ay co the co nguon goc do o nhiem binc sinh hoat,nong nghiep hoac t nc thai cong nghiep san xuat bot giat,chattay ra hay phan bon .Do o,ch tieu phosphate c ng dung trong viec kiemsoat mc o o nhiem cua dong nc.Viec xac nh phosphate rat can thiet trong van hanhcac tram s ly nc thai vatrong nghien cu o nhiem dong chay cua nhieu vungv ham lng phosphate cothe coi nh la mot lng chat dinh dng trong x ly nc thai .

1.2.1.2.1.2.1.2. Nguyen tacNguyen tacNguyen tacNguyen tac

Trong moi trng acid cac dang cua phosophate c chuyen ve dangorthophosphate va se phan ng vi ammonium molybdate e phong thch acidmolybdophosphoric, sau o acid nay se b kh bi SnCl2 cho molybdenum mauxanh dng.

PO43- +12 (NH4)2MoO4 + 24 H+ (NH4)3PO4.12MoO3 + 21NH4+ +12 H2O

(NH4)3PO4.12MoO3 + Sn2+ Molybdenum (xanh dng) + Sn4+

1.3. C1.3. C1.3. C1.3. Cac anh hngac anh hngac anh hngac anh hng

Trong ong mau phan tch ,tot nhat sat khong c vt qua 0,4 mg/l. Ham lngsilica hoa tan phai di 25mg/l. o uc cung la mot nguyen nhan tao kho khancho viec xac nh .Cromate va cac tac nhan oxy hoa manh nh peroxide co thelam nhat mau phan ng .Anh hng cac chat tren co the loai bo bang cach them0.1g acid sulfanilic vao mau trc khi them molybdate.

2. Dung cu ,thiet b va hoa chat2. Dung cu ,thiet b va hoa chat2. Dung cu ,thiet b va hoa chat2. Dung cu ,thiet b va hoa chat

2.1. D2.1. D2.1. D2.1. Dung cu va thiet bung cu va thiet bung cu va thiet bung cu va thiet b- Ong o o truyen suot.- Muong muc hoa chat .- Bep un.- Erlen.- Bi thuy tinh .- Pipet.


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2.2. H2.2. H2.2. H2.2. Hoa chatoa chatoa chatoa chata. Dung dch ch th phenolphthalein.b. Dung dch acid : can than cho 300ml H2SO4 am ac vao 600 ml nc cat vanh mc thanh 1000ml.c.Hon hp acid manh (strong acid solution):cho t t 300 ml H2SO4 am ac

vao 600 ml nc cat ,e nguoi .Them vao 4,0 ml HNO3 am ac nh mc thanh1000 ml.d. Ammonium persulfate (NH4)2S2O3 tinh the hoac potassium persulfate K2S2O8tinh the.e. Hydroxiyt natri NaOH 1Nf. Dung dch ammonium molybdate:

Hoa tan 25g (NH4)6Mo7O24.4H2O trong 175 ml nc cat .Can than them 280 mlH2SO4 am ac vao 400 ml nc cat,e nguoi.Cho dung dch molydate vao nhmc thanh 1000 ml.g. Dung dch tin chloride: can 2,5g SnCl2.2H2O trong 100 ml glycerol. un cachthuy va khuay en khi tan hoan toan.h. Dung dch photphate chuan:

Hoa tan 219,5 mg KH2PO4 khan (say kho 105o C mot gi) trong nc cat vanh mc thanh 1000 ml (1,00 ml=50,0 g P-PO4)

Dung 50 ml dung dch chuan pha loang thanh 1000 ml .Dung dch nay co nongo 1 ml =2,5 g p-PO4.

3. T3. T3. T3. Trnh t th nghiemrnh t th nghiemrnh t th nghiemrnh t th nghiem

a. Mau lac eu lay 50 ml hoac the tch phu hp .Cho vao 0,05 ml (1 giot) chat chth phenolphthalein.Neu mau co mau them vao t t dung dch sulfuric acid enkhi mat mau .Sau o them 1 ml dung dch sulfuric acid va 0,4 g (NH4)2S2O8 hoac0,5g K2S2O8.

un khoang 30 en 40 phut hoac the tch con khoang 10 ml .e nguoi them vao1 giot chat ch th phenolphthalein va trung hoa en mau hong nhat bang dungdch NaOH., nh the tch lai thanh 50 ml bang nc cat.

b. Lay 50 ml mau ,khong co mau va uc ,them mot giot chat ch thphenolphthalein. Neu mau chuyen sang mau hong ,them t t dung dch strongacid e mat mau.

c. Them vao 2,0 ml molybdate va 0,25 ml (5 giot ) tin chloride va lac eu .Toc ova cng o hien mau phu thuoc vao nhiet o. Do o nen gi loat dung dchchuan,mau va hoa chat cung nhiet o( chenh nhau khong qua 2oC) trongkhoang 20-30oC.


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d. e yen sau 10 phut( khong qua 12 phut) do o hap thu bang may quang pho ke bc song 690 nm.

e. Chuan b ng cong chuan:

STTSTTSTTSTT 0000 1111 2222 3333 4444 5555 6666ml dd P-PO4 chuan 0 1 2 3 4 5 -

ml nc cat 50 49 48 47 46 45 -

ml mau nc 8 7 6 5 4 8 50

ml dd molybdate 2,0 ml

ml SnCl2 0,25 ml= 5 giot

C (g) 0 2.5 5 7.5 10.0 12.5

C (mg/l) 0 0.05 0.1 0.15 0.2 0.25

o hap thu o bang maybc song 690nm

? ? ? ? ? ? ?

4. T4. T4. T4. Tnnnnh toanh toanh toanh toanT loat dung dch chuan,o o hap thu ,ve gian o A=f(C) ,s dung phng phapbnh phng cc tieu e lap phng trnh y = ax + b . T tr so o hap thu A mcua mau ,tnh nong o C m .Neu tr so A m cua mau vt qua cac tr so cua dungdch chuan ,phai pha loang en nong o thch hp.

5. C5. C5. C5. Cau hoiau hoiau hoiau hoi1. Y ngha cua phosphorus trong viec kiem soat o nhiem nguon nc ?2. S khac nhau gia orthophosphate,pholyphosphate va organic phosphorus ?3. So sanh ket qua phan tch cua mau nc thai sinh hoat ngay sau khi lay ve vamau a c bao quan trong nhieu ngay?


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OXI HOA TANOXI HOA TANOXI HOA TANOXI HOA TAN (DO)(DO)(DO)(DO)1. Gii thieu chung1. Gii thieu chung1. Gii thieu chung1. Gii thieu chung1.1. Y ngha moi trng1.1. Y ngha moi trng1.1. Y ngha moi trng1.1. Y ngha moi trng

DO (oxi hoa tan) la yeu to xac nh s thay oi xay ra do vi sinh vat k kh

hay hieu kh. ay la ch tieu quan trong nhat lien quan en viec kiem soat onhiem dong chay. Ngoai ra, DO con la c s kiem tra BOD nham anh gia mco o nhiem cua nc thai sinh hoat va nc thai cong nghiep.

Tat ca cac qua trnh x ly hieu kh phu thuoc vao s hien dien cua DOtrong nc thai, viec xac nh DO khong the thieu v o la phng tien kiem soattoc o suc kh e bao am u lng DO thch hp cho vi sinh vat hieu kh phattrien.

DO cung la yeu to quan trong trong s an mon sat thep, ac biet la tronghe thong cap nc va lo hi.

1.2. Nguyen tac1.2. Nguyen tac1.2. Nguyen tac1.2. Nguyen tacPhng phap Winkler cai tien da tren s oxi hoa Mn 2+ thanh Mn4+ bi lng oxihoa tan trong ncKhi cho MnSO4 va dung dch iodide kiem (NaOH + NaI) vao mau co hai trnghp xay ra:

- Neu khong co oxi hien dien, ket tua Mn(OH)2 co mau trangMn2+ + 2OH- Mn(OH)2 (tua trang) (1)

- Neu mau co oxi, mot phan Mn2+ b oxi hoa thanh Mn4+, tua co mau nau.Mn

2+

+ 2OH

-

+ 1/2O2 MnO2 + H2O (2)Hoac Mn(OH)2 + 1/2O2 MnO2 + H2O (3)

Mn4+ co kha nang kh I- thanh I2 t do trong moi trng acid. Nh vay, lng I2c giai phong tng ng vi lng oxi hoa tan co trong nc. Lng iod nayc xac nh theo phng phap chuan o bang thiosulfate vi ch th tinh bot.

MnO2 + 2I- + 4H+ Mn2+ + I2 + 2H2O (4)2Na2S2O3 + I2 Na2S4O6 + 2NaI (khong mau) (5)

Phng phap Winkler b gii han bi cac tac nhan oxi hoa khac nh: nitrite, sat

cac tac nhan nay cung co the oxi hoa 2I-

I2 a en viec nang cao tr soket qua. Ngc lai, tac nhan kh nh: Fe2+, sulfite, sulfide, lai oxi hoa I2 I-se lam thap gia tr ket qua.

ac biet ino nitrite la mot trong nhng chat ngan tr thng gap, no khong oxyhoa Mn2+ song khi moi trng co iodide va acid, NO2 no se oxy hoa 2I- I2,


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N2O2 tao thanh t phan ng lai b oxy hoa bi oxy kh tri qua mat thoang dungdch e lai cho NO2

2NO2 + 2I- + 4H+ I2 + N2O2 + 2H2OVa N2O2 1/2O2 + H2O 2NO2 + 2H+

Do o khi co NO2 trong mau, iem ket thuc khong the xay ra bnh thng khi cos bien oi lien tuc t 2I- I2 va ngc lai.

e khac phuc nhc iem tren cua pp Winker cai tien bang cach trong dd iodidekiem c them mot lng nho sodium azide:

NaN3 + H+ HN3 + Na+HN3 + NO2 + H+ N2 + N2O + H2O

Theo tien trnh nay NO2 b loai han.

2. Dung cu ,thiet b va hoa chat2. Dung cu ,thiet b va hoa chat2. Dung cu ,thiet b va hoa chat2. Dung cu ,thiet b va hoa chat2.1. D2.1. D2.1. D2.1. Dung cu va thiet bung cu va thiet bung cu va thiet bung cu va thiet b- 02 Chai DO- 02 Ong ong 100ml- 01 Buret

2.22.22.22.2Hoa chatHoa chatHoa chatHoa chata) Dd MnSO4: Hoa tan 480g MnSO4.4H2O (hoac 400g MnSO4.2H2O hoac 364 gMnSO4.H2O)trong nc cat pha loang thanh 1lt. e cho tan het khoang 3 tiengdd co mau hong.

b) Dd iodide-azide kiem: hoa tan 500g NaOH hoac (700g KOH) va 135g NaIhoac (150g KI) trong nc cat va pha loang thanh 1 lt. Them 10g NaN3 a choa tan trong 40ml nc cat.

c) axit sunfuric am ac

d) Dd Na2S2O3 0,025M: hoa tan 6,205g Na2S2O3.5H2O trong nc cat, them 1,5mlNaOH 6N hoac 0,4gNaOH vien pha loang thanh 1 lt.


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3.3.3.3. Trnh t th nghiemTrnh t th nghiemTrnh t th nghiemTrnh t th nghiem

- Lay mau vao ay chai DO 300ml, ay nut obo phan tren ra. Khong c e bot kh bamquanh thanh chai

- M nut, lan lt them2ml dd MnSO42ml Iodur-Azur kiem

- ay nut, ao chai t nhat 20s cho ket tua langyen khoang 2/3 chai

- i ket tua lang yen, m nut can than cho2ml H2SO4 am ac. ong nap ao manhchai.

- Khi ket tua a tan hoan toan, dung ong ong 100ml rot bo 97ml dung dch.nh phan lng con lai bang Natrithiosunphat en khi co mau vang nhat roi

them 5 giot ch th ho tinh bot. Tiep tuc nh phan cho en khi dung dch matmau xanh.

4.4.4.4. TTTTnhnhnhnh toantoantoantoan1ml Na2S2O3 0,025N = 1ml O2/L


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NHU CAU OXY SINH HONHU CAU OXY SINH HONHU CAU OXY SINH HONHU CAU OXY SINH HOC ( BIOLOGY OXYGEN DEMANDC ( BIOLOGY OXYGEN DEMANDC ( BIOLOGY OXYGEN DEMANDC ( BIOLOGY OXYGEN DEMAND BOD)BOD)BOD)BOD)

1. Gii thieu chung1. Gii thieu chung1. Gii thieu chung1. Gii thieu chung1.1 Y Ngha moi trng1.1 Y Ngha moi trng1.1 Y Ngha moi trng1.1 Y Ngha moi trng

Nhu cau oxy sinh hoa (BOD) la lng oxy can thiet e vi sinh vat oxy hoa cacchat hu c co kha nang phan huy sinh hoc trong ieu kien hieu kh. Khai niemco kha nang phan huy co ngha la chat hu c co the dung lam thc an cho visinh vat.

BOD la mot trong nhng ch tieu c dung e anh gia mc o gay o nhiem cuacac chat thai sinh hoat, nc thai cong nghiep va kha nang t lam sach cuanguon nc.

1.2 Nguyen tac1.2 Nguyen tac1.2 Nguyen tac1.2 Nguyen tac

S dung chai DO co V = 300ml. o ham lng DO ban au va sau 5 ngay u 20oC. Lng oxy chenh lech do vi sinh vat s dung chnh la BOD.

1.3 Cac anh hng1.3 Cac anh hng1.3 Cac anh hng1.3 Cac anh hng

Vi sinh vat nitrate hoa se s dung oxy e oxy hoa nit NH 3 thanh NO2- va NO3- ,do o co the lam thieu hut oxy hoa tan dan en BOD khong con chnh xac.

2. Dung cu, thiet b va hoa chat2. Dung cu, thiet b va hoa chat2. Dung cu, thiet b va hoa chat2. Dung cu, thiet b va hoa chat2.1 Dung cu va thiet b2.1 Dung cu va thiet b2.1 Dung cu va thiet b2.1 Dung cu va thiet b

Tu ieu nhiet BOD 20oC 1oCChai BODOng ong 100mlBuretPipet

Tu ieu nhiet BODTu ieu nhiet BODTu ieu nhiet BODTu ieu nhiet BOD2.2 Hoa chat2.2 Hoa chat2.2 Hoa chat2.2 Hoa chata. DD em phosphate: hoa tan 8,5g KH2PO4; 21,75g K2HPO4; 33,4gNa2HPO4.7H2O va 1,7g NH4Cl trong 500ml nc cat va nh mc thanh 1 lt.b. DD MgSO4 : hoa tan 22,5g MgSO4.7 H2O trong nc cat, nh mc thanh 1 lt.c. DD CaCl2 : hoa tan 27,5g CaCl2 trong nc cat, nh mc thanh 1 lt.d. DD FeCl3 : hoa tan 0,225g FeCl3.6H2O trong nc cat, nh mc thanh 1 lt.


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e. DD H2SO4 1N hoac NaOH 1N e trung hoa mau co tnh kiem hoac tnh acid.f. DD Sulfit natri: hoa tan 1,575g Na2SO3 trong 1 lt nc cat.g. DD Acid glutami (glucose glutamic acid solution): say glucose va glutamicacid trong 1h nhiet o 103oC, them 150mg glutamic acid vao nc cat va phathanh 1lt.

h. DD ammonium chloride: hoa tan 1,15g NH4Cl trong nc cat, chnh pH = 7,2bang NaOH va pha loang thanh 1 lt. DD cha 0,3mg N/ml.

3. T3. T3. T3. Trnh t th nghiemrnh t th nghiemrnh t th nghiemrnh t th nghiem

a. Chuan b nc pha loang (nc cat c suc kh bao hoa oxy)

S dung moi dung dch phosphate, MgSO4, CaCl2, FeCl3 la 1ml cho 1 lt n1ml cho 1 lt n1ml cho 1 lt n1ml cho 1 lt nc catc catc catc catbao hoa oxy va gi 20oC 1oC (nc pha lo

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