10 Science Sa 2 Demo

8/12/2019 10 Science Sa 2 Demo

1/20


2/20

SCIENCE(Class 10)

Index

CBSE Chapter-wise Test Papers solved unsolved

1. Carbon and Its Compounds 001 1002. Periodic Classification of Elements 015 1053. Ho do !r"anisms #eproduce 020 110$. Heredit% and E&olution 03' 1155. e Human E%e and Colourful *orld 051 120'. +i"t,#eflection and #efraction 05- 125. !ur En&ironment 03 130-. /ana"ement of atural #esources 0-- 135

CBSE Sample Papers (Solved)

1. ample Paper issued b% CE 1$02. ol&ed ample Paper 01 1513. ol&ed ample Paper 02 1'2$. ol&ed ample Paper 03 155. ol&ed ample Paper 0$ 1-'. ol&ed ample Paper 05 1

Other Papers

1. 4nsol&ed ample Paper (1,5) 202. Pre&ious ear Papers (1,-) 2$2


3/20

Material downloaded from http://myCBSEguide.comand http://onlineteachers.co.in

Portal for CBSE Notes, Test Papers, Sample Papers, Tips and Tricks

CBSE TEST PAPER-01

CLASS - X (Carbon and its compound)

1. Soaps are formed by the saponification of

(a) Alcohols (b) simple ester (c) carboxylic acids (d) glycerides

(1)

2. The functional group of butanone is

(a) Carboxyl (b) ketonic (c) aldehydic (d) alcoholic

(1)

. !n"yme #hich con$erts starch into glucose is

(a) %ymase (b) &altase (c) 'iastase (d) n$ertase

(1)

. The first compound to be prepared in the laboratory #as

(a) &ethane (b) !thyl alcohol (c) acetic acid (d) *rea.

(1)

+. The *,AC name of3

CH CHO is

(a) Acetaldehyde (b) -ormaldehyde (c) &ethyl formaldehyde (d) !thanal.

(1)

.

/ame the follo#ing compounds. (a)|

H

H C O = (b) 3 2CH CH Cl

(2)

0. 'efine soaps (2)

. /ame the second member of alkynes family 3i$e its structure (2)

4. 3i$e a chemical test to distinguish bet#een !thane and ethene. (2)

15. Complete the follo#ing reaction

(i) 2 42 2 2 H SO

H C CH H O= +

(ii) 2HC CH Br +

(iii)2 5

C H OH Na+

()

11. 6hat is the role of concentrated 2 4H SO in the esterification reaction ()

12. 6hat #ill be the formula and electron dot structure of cyclopentane ()

1. 'ra# the structures of the follo#ing compounds

(a) !thanoic acid (b) 7romopentane (c) 7utanone

()

1. 'efine fermentation. /ame the en"yme #hich con$erts

(a) milk into curd (yogurt)

(b) Cane sugar into glucose and fructose

(c) glucose into ethanol

(+)

(001)


4/20



CBSE TEST PAPER-01


[ANSERS!

Ans1. (d)

Ans2. (b)

Ans. (a)

Ans. (d)

Ans+. (d)

Ans. (a) &ethanol

(b) Chloroethane

Ans0. Soaps are the sodium or potassium salts of long chain fatty acids. These are

represented by 8C99/a or 8C998

Ans. The second member of the alkyne family is propyne. ts structural formula is

3CH C CH

Ans4. !thene decolori"es the yello# colour of bromine #ater #hile ethane does not.

Ans15. (i) 42

2 2 2 3 2= + H SO

H C CH H O CH CH OH

(ii)| |

2| |

2

Br Br

Br Br

HC CH Br H C C H +

(iii) 2 5 2 5 22 2 2C H OH Na C H ONa H + +

(002)


5/20



Ans11. n esterification reaction a carboxylic acid reacts #ith alcohol to form ester and

#ater in the presence of concentrated sulphuric acid. This reaction is re$ersible

and this re$erse reaction is called ester hydrolysis.

Concentrated sulphuric acid being a strong dehydrating agent remo$es #ater

from the reaction mixture. As a result: the reaction proceeds only is the for#ard

direction to form ester.

2 4

2

Acid Alcohol Ester

+ +conc H So

RCOOH ROH RCOOR H O

Ans12. t is a cyclic compound #ith formula 5 12C H . The structure of the compound is

represented as

Ans1. (a)||

OH

HH C C OH !thanoic acid

(b) 3 2 2 2 2 CH CH CH CH CH Br 7romopentane

(c)||

3 2 3

O

H C C CH CH 7utanone

Ans1. The preparation of ethyl alcohol from sugar ( )12 22 11C H O is kno#n as

fermentation.

(a) ;actase con$erts milk into curd

(b) n$ertase con$erts cane sugar into glucose and fructose

(c) %ymase con$erts glucose into ethanol.

C

C

C

C

C

H

H

HH

H

H

H

H

H

H

(003)


6/20



CBSE TEST PAPER-02


1. Rectified spirit is

(a) 50% ethanol (b) 80% ethanol

(c) 95% ethanol (d) 40 to 50% ethanol

(1)

2. Dilute alkaline !n"4solution is

(a) an o#idisin$ a$ent (b) a reducin$ a$ent

(c) a bleachin$ a$ent (d) none of these

(1)

. &he b' product in soap industr' is

(a) soprene (b) th'lene $l'col

(c) $l'cerol (d) butane

(1)

4. *n e#a+ple of soap is

(a)15 31

C H COONa (b)3

CH COONa

(c) 6 5C H COONa (d) 17 35 3C H OSO Na

(1)

5. &he nu+ber of ,- bonds in ethane ,2/+olecule are

(a) 4 (b) /

(c) 8 (d) 10

(1)

/. rite the structures of

(i) thanoic acid (ii) e# anal

(2)

. a+e the follo3in$ co+pounds

(a) 3 0H

CH C = (b) 3 2CH CH OH

(2)

8. hich or$anic co+pound is added to +ake ethanol unfit for drinkin$ purposes

hat is the na+e of the +i#ture for+ed

(2)

9. rite a test to identif' the presence of ethanoic acid (2)

10. i6e na+es of the follo3in$ ()

(004)


7/20



(a) *n aldeh'de deri6ed fro+ ethane

(b) etone deri6ed fro+ butane

(c) ,o+pound obtained b' the o#idation of ethanol b' chro+ic anh'dride

11. hat is +eant b' denatured alcohol

hat is the need to denature alcohol

()

12. rite che+ical e7uations of the reactions of ethanoic acid 3ith

(a) odiu+ (b) odiu+ carbonate

(c) thanol (d) &he presence of conc 2o4

()

1. ,o+plete the reaction and na+es of the products for+ed

(i) 3 + heatCH COOH NaOH

(ii)4

2 5 2

alkaline

KMnOC H OH O+

(iii) 2 43 2 5 4 + Conc H SO

CH COOH C H O

()

14. (a) a+e the $as e6ol6ed durin$ fer+entation process

(b) hat role is pla'ed b' 'east in the con6ersion of cane su$ar (,1222"11) to

ethanol

(c) o3 +a' the follo3in$ be obtained fro+ pure ethanol #press che+ical

reactions b' the che+ical e7uations.

(i) odiu+ etho#ide (ii) th'l ethanoate (iii) thanal

(5)

(005)


8/20



CBSE TEST PAPER-02


[ANSERS!

*ns1. (c)

*ns2. (a)

*ns. (c)

*ns4. (a)

*ns5. (b)

*ns/. (i) ,-||O

C-on

(ii) ,-,2-,2-,2-,2-||O

C-

*ns. (a) thanal

(b) thanol

*ns8. !ethanol 3hich is hi$hl' poisonous is added to +ake ethanol unfit for drinkin$

purpose. &he +i#ture is called +eth'lated spirit or denatured alcohol.

*ns9. Dip a strip of blue lit+us paper in the solution of ethanoic acid. ts colour 3ill

chan$e to red.

*ns10. (a) thanal (,,")

(b) utanone (,,",2,)

(c) thanal (,,")

*ns11. th'l alcohol 3hich contains s+all a+ount of +eth'l alcohol or copper sulphate is

called denatured alcohol. &he purpose of denaturin$ of alcohol is to +ake it unfit

for drinkin$ purposes.

(006)


9/20



*ns12. (i) 2,,"":2a 2,,""a:2

(od. thanoate)

(ii) 2,,"":a2," 2,,""a:,"2:2"

(od. thanoate)

(iii) ,,"":,25" 2 4 conc H So

,,"",25

(th'l ethanoate)

*ns1. (i) ,,"":a" Heat ,,""a:2"

(od. thanoate)

(ii) ,25":"2alkaline

KMnOH,,"":2

(thanoic acid)

(iii) ,,"":,25" 2.

Conc H Sol

,,"",25:2"

(th'lethanoate)

*ns14. (a) ,"2$as is e6ol6ed acco+panied b' brisk effer6escence.

(b) ;east is the source of en


10/20



CBSE TEST PAPER-03


1. The odour of acetic acid resembles that of

(a) Rose

(b) Burning Plastic

(c) Vinegar

(d) Kerosene

(1)

2. Diamond is not a good conductor of electricity because

(a) t is !ery hard

(b) ts structure is !ery com"act

(c) t is not soluble in #ater

(d) t has no free electrons to conduct electric current.

(1)

$. %lcohols can be "roduced by the hydration of

(a) %l&enes

(b) al&ynes

(c) al&anes

(d) acids

(1)

'. The P% name of *$*+ is

(a) %cetaldehyde

(b) formaldehyde

(c) methyl formaldehyde

(d) ethanol

(1)

,. P% name of first member of homologous series of &etones is

(a) -thanone

(b) methanone

(c) Pro"anone

(d) Butanone

(1)

(008)


11/20



. /hat are the "ro"erties of carbon #hich lead to huge number of carbon

com"ounds #e see around us0

(2)

. ame the follo#ing com"ound(a) *$3*23Br

(b) $ 2 2* * * *

(2)

4. /hy con!ersion of ethanol into ethanoic acid is an o5idation reaction0 (2)

6. % mi5ture of ethyne and o5ygen is used for #elding. an you 7ustify #hy a

mi5ture of ethyne and air is not3used0

(2)

18. /hat is a homologous series0 9tate any t#o characteristics of homologousseries0

($)

11. :i!e the structural formulas for

(i) ;ethyl -thanote

(ii) -thyl ethanoate

/rite t#o uses of -ster0

($)

12. /hat are en


12/20



CBSE TEST PAPER-03


[ANSERS!

%ns1. (c)

%ns2. (d)

%ns$. (a)

%ns'. (d)

%ns,. (c)

%ns. (i) 9elf lin&ing "ro"erty called catenation

(ii) arbon is tetra!alent and can readily unite #ith atoms li&e hydrogen> o5ygen

etc by electron sharing

%ns. (i) Bromoethane

(ii) *e5313 yne

%ns4. -thanoic acid has one +2> atom more and t#o hydrogen atoms less then ethanol.

%nd loss of hydrogen is &no#n as o5idation and gain of o5ygen is &no#n as

o5idation. Therefore it is an o5idation reaction.

%ns6. /hen ethyne is burnt in o5ygen> large =uantity of heat and light is "roduced. The

heat e!ol!ed can be used for gas #elding #hich is used for #elding bro&en "ieces

of articles. %s air contains mi5ture of nitrogen and o5ygen and nitrogen #hich is

more in amount does not su""ort combustion. Therefore it is al#ays better to use

o5ygen for the combustion of ethyne.

%ns18. % series of similarly constituted com"ounds in #hich the members "resent ha!e

the same functional grou"> same chemical "ro"erties and any t#o successi!e

members is a "articular series differ in their molecular formula by *2grou".

(i) 9ame functional grou"(ii) 9ame chemical "ro"erties.

(010)


13/20



%ns11. (i)||

3

O

H C OCH

(ii)3 2 5

CH COOC H

ses of esters?

(1) -sters ha!e "leasant smell. These are used as fla!ouring agents and alsoin "erfumes.

(2) -sters of glycerol &no# as triglycerides are used in the manufacture ofsoa"s. This reaction is called sa"onification reaction.

%ns12. -n


14/20



CBSE TEST PAPER-04


1. An unknown compound has the smell of vinegar. Identify it. (1)

2. Out of butter and groundnut oil which is unsaturated in nature (1)

!. "hich has triple bond# 2 4 3 4 3 6, ,C H C H C H (1)

$. "hich substance is added for the denaturation of ethyl alcohol (1)

%. "hich ions are responsible for making water hard (1)

&. "hy carbon and its compounds are used as fuels in most cases (2)

'. A compound has the molecular formula 3 6C H O with structural formula

3 2CH CH CHO . ive its I*+A, name. ,an another compound have the same

molecular formula ive the structure and I*+A, name of that compound also.

(2)

-. "hy ,O group cannot be present in the middle of the carbon atom chain (2)

/. 0wo carbon atoms cannot be linked to each other by more than three covalent

bonds. "hy

(2)

1. "rite three difference between ethanol and ethanoic acid on the basis of

chemical properties

(!)

11. iven a chemical test to distinguish between

(i) thane and ethene (ii) thanol and ethanoic acid (iii) 3oaps and 4etergents

(!)

12. 5ame the functional groups present in the following compounds

(i)3 2 2

CH CH CH OH (ii)3 2 2

CH CH CH COOH (iii)3 2

CH CH CHO

(!)

1!. "hat are esters "rite an e6uation to show the formation of ester (!)

1$. (a) "hy does carbon form largest number of compounds

(b) "hy are some of these called saturated and other unsaturated compounds

(c) "hich of these two is more reactive

(d) "rite the names of the following compounds

(i) 2 2CH CH Br (ii) 3 CH CH CH CH C C H

(%)

(012)


15/20



CBSE TEST PAPER-04


[ANSERS!

Ans1. Acetic acid

Ans2. roundnut oil

Ans!.3 4

C H

Ans$. 7ethyl Alcohol

Ans%. 2Ca + and 2Mg +

Ans&. ,arbon burns in o8ygen or air to form 2CO gas. 0his reaction is highly

e8othermic that is why different form of coals are used as fuels

Ans'. 0he I*+A, name of is propanal.

Another similar compound is 9 is.

||

3 3

O

CH C CH (+ropanone)

and 9 are related to each other as functional isomers.

Ans-. 0he ,O group is a terminal functional group since three valencies of the ,:

atom are already satisfied# so this group cannot be present in the middle of the

chain.

Ans/. "hen two carbon atoms are to linked by four covalent bonds their nuclei come

so close to one another that the force of repulsion between them will push these

apart. As a result# a stable molecule will not be formed.

Ans1. (i) On adding a small amount of 3NaHCO to ethanoic acid ,O2gas is evolved

with brisk effervescence and no such reaction takes place in case of ethanol

3 3 3 2 2+ + +CH COOH NaHCO CH COONa CO H O

(ii) thanol is neutral so does not bring any change in the colour of litmus paper

but ethanoic acid is acidic and changes the colour of a blue litmus strip to

red when dipped in it.

(013)


16/20



(iii) thanoic acid reacts with 5aO and ;O to form salt and water where as

ethanol fails to react.

3 3 2

3 3 2

+ +

+ +

CH COOH NaOH CH COONa H O

CH COOH KOH CH COOK H O

Ans11. (i) thane decoloriromoethane

(ii) e8:1:yne

(014)


17/20



CBSE TEST PAPER-01

CLASS - X (Periodic classification of elements)

1. Arrange the following in descending atomic size Na, Mg, K (1)

2. Give the name and electronic configuration of second alali metal! (1)

". #hat is the similarit$ in the electronic configuration of Mg, %a and &r! (1)

'. #hich is igger in size Na, Na (1)

*. Name three elements which ehave as metalloids! (1)

+. Alali metals do not form diositive ions wh$! (2)

-. #h$ nonmetals are called electro negative elements! (2)

/. 0ow were the ositions of different isotoes decided in the modern eriodic

tale!

(2)

. 0$drogen is regarded as a rogue element in the eriodic tale. iscuss. (2)

13. %alcium is an element with 4 5 23

(a) 6s it a metal or a nonmetal!

() #ill its size e igger or smaller than that of otassium!

(c) write the formula of its chloride

(")

11. (a) Name the elements resent in the third eriod and classif$ them into metals

and nonmetals.

() 7n which side of the tale do $ou find the metals!

(c) 7n which side of the tale do $ou find the nonmetals!

(")

12. 8ale is a art of eriodic tale

0 0e

9i :e : % N 7 ; Ne

Na Mg Al &i < & %l Ar=se this tale and e>lain wh$

(a) 9i and Na are considered as active metals

() Atomic size of Mg is less 8han that of Na

(c) ;luorine is more reactive than chlorine.

(")

1". #rite two ma?or shortcomings of Mendeleev@s eriodic tale! 0ow have these

een removed in the modern eriodic tale!

(")

(015)


18/20



CBSE TEST PAPER-01


[ANSERS!

Ans1. K, Na, Mg

Ans2. &odium (Na) (2, /, 1)

Ans". All the elements have two electrons in their valence shell.

Ans'. Na

Ans*. Arsenic (As), Antimon$ (&), Germanium (Ge)

Ans+. Alali metals resent in Grou 1 so 1- has onl$ one valence electron. :$ loosing

one e8he$ acuire the configuration of the nole gas element and hence do not

form disositive ions.

Ans-. Nonmetals are called electronegative elements since their atoms form negative

ions $ acceting electrons

Ans/. All the isotoes have same atomic numers in modern eriodic tale the elements

have een allotted laces ased on their atomic numers. 8herefore all the

isotoes of an element have een assigned the same osition in the modern

eriodic tale.

Ans. 0$drogen is regarded as a rogue element in the eriodic tale ecause till toda$ its

osition is not satisfactor$. Although it has een laced on the to of alali metals

on the asis of electronic configuration, ut it is nonmetal and also resemles

halogens of grou 1-.

Ans13. 4 5 23 is 2, /, /, 2

(i) 6t is a metal which has two valence electrons it is resent in grou 2

(016)


19/20



(ii) :oth otassium (K) and calcium (%a) are resent in fourth eriod. &ince atomic

size decreases along a eriod calcium is smaller in size.

(iii) 8he valenc$ of calcium is 2 and its formula.

Ans11 (a) 8he elements are

Na Mg Al &i < & %l Ar

() 8he metals are laced mostl$ on the left side of the tale.

(c) 8he nonmetals are laced on the right side of the tale.

Ans12. (a) :oth 9i and Na are active elements since their atoms have onl$ one electron

in their valence shells. 8he$ readil$ lose this electron to have the

configuration of the nearest nole gas element.

() Mg is laced after Na is the same eriod (third). As the atomic size decreases

along a eriod, the size decreases along a eriod. 8he size of Mg is less than

that of Na.

(c) :oth ; and %l elong to Grou 1-. &ince fluorine is more electronegative than

chlorine, it is therefore more reactive also.

Ans1". 8he two ma?or short comings of Mendeleev@s eriodic tale were

(i) 6t could not ?ustif$ the osition of h$drogen is the eriodic tale

(ii) 6t could not assign roer osition to the different isotoes of the same

element

8he main reason for these short comings was the asis of the Mendeleev@s eriodic

tale. 6t regarded atomic masses of the elements as the asis of classification. 8he

modern eriodic tale regards atomic numers of the elements as the asis of

classif$ing the elements. 6t removed oth the short comings from the tale.

(017)


20/20



CBSE TEST PAPER-02


1. Which of the following has maximum atomic size?

(a) K (b) Ca (c) Al (d) P

(1)

2. he law of octa!es was "#o"osed b$

(a) %ewland (b) &obe#iene#

(c) 'othe# e$e# (d) endlee!e

(1)

. he numbe# of "e#iods in the long fo#m of the "e#iodic table is

(a) * (b) + (c) 1, (d) 1-

(1)

. Which of the following elements has maximum metallic cha#acte#?(a) 'i (b) % (c) %a (d) P

(1)

/. Which of the following is the most #eacti!e halogen?

(a) 0 (b) Cl (c) # (d) (1)

*. Wh$ do elements in a g#ou" show same !alenc$? (2)

+. Wh$ a#e the membe#s of g#ou" 1 3nown as al3ali metals? (2)

-. 4ow does metallic cha#acte# of the elements !a#$ (i) n a g#ou" (ii) n a "e#iod? (2)

5. %ame othe# elements which belong to the same famil$ as

(i) Calcium (ii) Ca#bon.

(2)

1,. 4ow would tendenc$ to gain elect#ons change as $ou go down in a g#ou"? ()

11. wo elements 6 and 7 belong to 8#ou" 1 and 8#ou" 2 #es"ecti!el$ in the same

"e#iod. Com"a#e them with #es"ect to9

(a) he numbe# of !alence elect#ons (b) :alenc$ (c) metallic cha#acte#

(d) ;ize of the atoms (e) 0o#mulae of thei# oxides and chlo#ides.

()

12. he following table shows the "osition of six elements A< < C< &< = and 0 in the

"e#iod table.8#ou"s

Pe#iods

1 2 to 12 1 1 1/ 1* 1+ 1-

2 A C

& = 0

>sing the table answe# the following

(a) Which element will fo#m onl$ co!alent com"ounds?

(b) Which element is a metal with !alenc$ 2.

(c) Which clement is a nonmetal with !alenc$ .

(d) @ut of & and = which has bigge# atomic #adius and wh$?

(e) W#ite a common name fo# the famil$ of elements C and 0

()

Documents

10 Science Sa 2 Demo