MARKING SCHEME CHEMISTRY WAJA
CHAPTER 5: CHEMICALS FOR CONSUMERSAnswer
A: SOAP AND DETERGENTActivity 1
1. Sodium, potassium
2. RCOO-Na + or RCOO-K+3. Sodium palmitate, potassium
palmitate,potassium stearate,
4. calcium and magnesium
5. saponification
6. sodium hydroxide l
7. surface tension
Activity 2 1. Procedure: Arrangement in correct sequence:
HBCADFIGE2. Potassium hydroxide3. To reduce the solubility of
soap
4. Palm oil + sodium hydroxide soap + glycerol
5. corn oil/coconut oil/ olive oilActivity 3 Match the questions
with the correct answers.
1 State an example of detergent. scum
2What is hard water?Biological enzyme
3Name the additive that removes organic stain.Optical
whitener
4What is the advantage of using detergent as a cleaning
agent?Sodium alkylbenzene sulphonate
5Name the three materials used to prepare
detergent.Alkylbenzene,sulphuric acid and sodium hydroxide
6
State the observations when a little soap is dissolved in hard
water.Calcium of magnesium salts of detergent are soluble.
7An additive that prevents the fading of color.Works effectively
in hard water.
8An additive that reduces the formation of foam.Foam control
agent
9Explain why detergent can be used in hard water.Water that
contains calcium ion or magnesium ions
Activity 4Surface tension
Hydrophobic
Hydrophilic
Scrubbing
Smaller droplets
EmulsionActivity 5
Differences between Soap and DetergentSOAPDETERGENT
DEFINITIONsodium sulphonic
EXAMPLESSodiumpotassium
PREPARATIONsodium hydroxide and fat/oilSodium alkyl sulphate
SOURCES OF RAW MATERIAL naturalsynthetic
EFFECTIVENESS hard
FORMATION OF SCUM IN HARD WATERscummagnesium
EFFECT TO ENVIRONMENTBiodegradableNon-biodegradable.
Activity 6 Type of additiveExampleFunction.
To remove protein stains such as blood.
Whitening agentTo convert stains into colorless substances.
To add brightness and whiteness to white fabrics.
Sodium tripolyphosphateTo enhance the cleaning efficiency of
detergent by softening the water
Suspension agent
To add to the bulk of the detergent and enable it to be poured
easily.
To control foaming in detergent.
fragrance -
Activity 71Procedure
Two beakers are filled with hard water. Soap is added to one of
the beaker and detergent is added to another. Dirty cloths are
placed into the beakers and agitated.
Observations :
Detergent in hard water
Soap in hard water
1. Cloth is cleaned fast
1. Cloth is cleaned slowly
2. No formation of scum
2.Scums forms
3. The water turns dirty
3. Water is less dirty
Conclusion :
Detergent cleans stains more effectively compared to soap
2. a) saponification
b) ester
c) COO-3. Concentrated potassium hydroxide4. i) hydrophobic ii)
Hydrophilic head dissolves in water
Hydrophobic tail dissolves in grease
Detergent ions reduce the surface tension of water.
Activity 81. prevent spoilage, to improve , taste , texture
2. Types of food additives: Preservative, Antioxidant,
Flavoring, Stabilizer, thickener, Dye.3.Types of food
additivesFunctionsExamples
Preservatives
Antioxidants
FlavoringsSugar, salt, vinegar, MSG, aspartame.
StabilizersLecithin, mono and di-glycerides.
ThickenersAcacia gum,pectin,gelatin xantha gum
Dyes Tartrazine,brilliant blueFCF,azo dyes
4. ADVANTAGESDISADVANTAGES
1. Make food stay fresh longer, look nicer and taste better.
2. Make seasonal crops and fruits available throughout the
year.
1. Some food additives are associated with diseases like cancer,
asthma, allergies and hyperactivity.
2. It makes food less nutrititous.
5a) sugar, salt, spice, permitted modified starch
b)Food additives present Type of food additives
sugarPreservative/flavoring
saltPreservative/flavoring
vinegarflavoring
starch modifiedthickener
6a) i) aspartame ii) honeyb) i) To add or restore the color in
food ii) to enhance its visual appeal and to match consumer
expectationACTIVITY 9Traditional medicines
Complete the table below using the words in the box.
PlantUses/function
garlicFor preventing flu attack or asthma attack.
For reducing high blood pressure.
gingerFor treating stomach pain due to wing in stomach
For supplying heat energy to keep the body warm.
Aloe veraFor treating itchy skin
For treating burns on the skin.
lemonFor treating boils or abscesses on the skin
For preventing flu attack
For treating skin diseases
quinineFor treating malaria
For preventing muscle cramps
ginsengAs tonic to improve the overall health of human
beings
For increasing energy, endurance and reducing fatigue
Lemon grassHas antibacterial and antifungal properties
For treating coughs
Tongkat aliAs a tonic for after birth and general health
To increase male libido
Misai kucingTo treat gout, diabetes and rheumatism
Hempedu bumiTo treat diarrhoe,fever and diabetes
selasihTo treat coughs colds and bronchitis.
Activity 10a ) To relieve mild to moderate pain such as
headache,muscle and joint
paint,backache and period pains
b) antibiotic.
To treat tuberculosis,whooping cough and some forms of
pneumonia
c) Sedate,calm or relax or induce sleep.
To treat pschyhiatraic illness such as schizophrenia.
Activity 11 Refer to F5 text book page 200 -201Activity 121 a.
insulin
b. streptomycin , penicillin
c. tranquilizer
d. codeine
2. a. gonorrheab. streptomycin, penicillin
c. all the antibiotic prescribed by the doctor must be
consumed
d. to ensure all the bacteria are killed
3. a. to relieve pain without causing numbness or affecting
conciousness. b. gastric patient and children
c. to cause brain and liver damage if given to children with flu
or chicken pox. d. paracetomol
4. A type of hormone used to cure diabetes mellitus.
5.
Traditional medicineModern medicine
Usually not processedProcessed in laboratory
Derived from plant and animalSynthesized based on substances
found in nature.
6. a. To kill or inhibit the growth of bacteria.
b. this is because these antibiotic are broken down by the acid
in the stomach.Activity 13
1. MedicinefunctionexampleSide effects
StimulantTo reduce fatiguemetithylphenidatePhysical and
psychological dependence
AntidepressantTo reduce tension and
anxietybarbiturateaddiction
AntipsychoticTo treat psychiatric
illnesschlorpromazinedizziness
2.
chemicalsProper management
detergentUse biodegradable detergent
Food additiveAvoid consuming to much salt and sugar
medicinesNo self medication
3. Tomato sauce, salt,xanthan gum
4. falvoring agent:: tomato sauce and salt
Thickener : xanthum gum
Activity 14a(i)R
a(ii)Stomach pain due to wind in the stomach
a(iii)Extract the juice from the rhizome and drink
b(i)X : Analgesics
Y : Antibiotics
Z : Psychotherapeutic medicine
(ii)Can cause bleeding in the stomach
(iii)The bacteria will attack the patient with the same disease
again
iv)Calm down the patients emotion
Lemon grass, lemon, garlic, aloe vera , ginseng , tongkat ali,
ginger , quinine,
pegaga, misai kucing, hempedu bumi,selasih,
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