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Transcript of 14 Chemical for Comsumers
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CHAPTER 5 : CHEMICALS FOR CONSUMERS
Chemistry Module 2009@ Hak Milik JPN Pahang
CHEMICALS FOR CONSUMERS
Soap and Detergent
Food additiveMedicine
5.1
5.2
5.3
1. Define the soap.2. Define detergent. 3. Describe soap preparation process4. Describe detergent preparation process5. Describe the cleansing action of soap. 6. Describe the cleansing action of detergent 7. Define the hard water. 8. Explain why detergent more effective than soap
when cleaning using the hard water? 9. Identify the additives in detergent and their
respective functions
1. Define food additive. 2. What information we can get from the food covers. 3. List the types of food additive and then gives one example for each type of food additive respectively.
1. What is medicine? 2. State the difference between modern medical and traditional medical. 3. State four type of modern medicine. Give functions of each type of the medicine. List 2 example of medicine for each type of the medicine respectively. 4. Gives three example of traditional medicine and their usage respectively.
Analyse soap and detergent
Understanding medicine Evaluate the
use of food additivesu
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B. 5.1
Act 5.3
Act 5.2
Chemistry Module 2009@ Hak Milik JPN Pahang
SOAP AND DETERGENT
Definition of soap
Preparation of soap (saponification)
Experiment 5.1 pg 118
O
CH2 – O – C – R
O
CH2 – O – C – R + 3NaOH
O (alkali)
CH2 – O – C – R
(oil)
CH2OH O
CH2OH + 3 NaO-C - R
CH2OH (Glycerol) (Soap)
Palm oil +NaOH
Glass rod
Panaskan
Salt of sodium or potassium of any carboxylic acid/fatty acid
Cleansing action of soap and detergent
Comparing the cleaning effect by soap and detergent
In water, soap ionized to form soap ion and sodium ion. Soap ion has hydrophilic (ionic) and hydrophobic (hydrocarbon) part. In the cleansing process, hydrophobic parts are out of the water surface while hydrophilic parts are in the water. The surface tension of water will be less to make the surface of the cloth to be wet easily. Hydrophobic part dissolved in the oily dirt, while hydrophilic parts are in water. When rinsing, water pull the hydrophilic, hydrophobic and oily dirt away from the cloth.
Heat
Soap
Detergent
Definition of detergent:
Preparation of detergent, sodium alkylbenzene sulphonate;Detergent
additive
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B. 5.2
Chemistry Module 2009@ Hak Milik JPN Pahang
DETERGENT
What is detergent?
Preparation of detergent (straight chain)
Detergent additive
Effectiveness of detergent as a cleansing agent
Detergent and the environmental pollutions
O O R – O – S – OH + NaOH R – O – S – O-Na+ + H2O O OAlkyl sulphonic acid Sodium alkyl sulphate (detergent)
O O
R - O - S - OH + NaOH R - O - S – O-Na+ + H2O O O
Alkylbenzene sulphonic Sodium alkylbenzene sulphonate
Biological enzyme – protein digestWhitening agent – bleaching i.e
Sodium per borateWater softener – Bubble stabilizer – Fluorescence – Perfume -
Detergent more effective than soap in the hard water because the reaction of detergent ion with calcium ion, magnesium ion or iron ion form soluble salt. (Using soap with hard water will form sticky scum).
1. Bubble at the water surface prevent dissolving of oxygen in water …
2. Non biodegradation detergent at the water surface dissolved natural oil at the bird fur …
3. Detergent additive become fertilizer to the water weed and promoting growing of water weed and then …
Comparing soap and detergent
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B. 5.3
Chemistry Module 2009@ Hak Milik JPN Pahang
FOOD ADDITIVES
Definition of food additive
Food additive from natural sources
Types of food additive, function and the examples
Substances added to the food in order to make it last longer, better smell, taste and colour
Salt, sugar, vinegar, fenugreek, clover, aniseed, cinnamon, buah pelaga, turmeric etc
Types of Food additives Function Preservatives Prevent or slow down spoilage of food caused by microorganisms.
Sodium nitrite (meat preservatives) sodium benzoate (preservatives for various sauces
Antioxidants To slow down oxidation process of food Ascorbic acid /vitamin c used in cordial drink
Flavouring agent To make food more delicious. Monosodium glutamate, MSG (flavour and aroma of food), saccharin and Aspartame (gives sweet flavour of food).
Stabilizers and thickening agents
To improve appearance and firm texture of food that is smooth and uniform. Acacia gum, azo compounds
Dyes To make food look more attractive.
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B. 5.4
example
definition
Chemistry Module 2009@ Hak Milik JPN Pahang
Barbiturate, tranquilizer
MEDICINE/DRUG
Definition of medicine
Traditional Medication
Modern Medication
Type of Modern Medicine
Chemicals that used to treat patient.
Base on effectiveness without knowing chemicals. Effectiveness depends on practices and belief without scientific proof.
Chemicals , effectiveness and side effect are well known by research.
Traditional medicine
Ginseng -- For ..Pudina --Aloe vera –Kuinina --Garlic --Ginger --etcl.
Analgesic
Antibiotic Psychiatric medicine
Hormone
Reduce pain and fever
Preparation of aspirin:
Salicylic acid + ethanoic anhydride
Acetylsalicylic acid + ethanoic acid (aspirin)
Aspirin, paracetamol, codeine
Kill or inhibit growth of microbe (except virus)Penicillin,
streptomycin
Effected onto brain and nerve system
Stimulant
Depressant
Amphetamine
Organic material that has fisiology effect
Insulin, cortisone
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CHAPTER 14: CHEMICALS FOR CONSUMERS
A. SOAP AND DETERGENT
1. Definition:
(i) Soap: A sodium or potassium salt of long-chain……………….(ii) Detergent: A sodium or potassium salt of …………………….acid or
………………….acid.
2. Soap preparation process:
Soap are prepared by hydrolysing fats or oils under alkaline condition. This reaction is called……………………
The process involves boiling fats or oils with ………………………………or ……………………………………..to produce ………………….and the salts of fatty acids which are the ……………
Write down the general equation for this reaction ;
+ NaOH +
Oil or fat alkali Glyserol Soaps
3. Detergent preparation process:
During the preparation of detergents, a long-chain hydrocarbon obtained from ……………………………is converted into an organic acid through a series of steps.The organic acid is then neutralized with …………………………..solution to produce a detergent.
4. Draw the general formulae for two common detergents
A sodium alkyl sulphate A sodium alkylbenzene sulphonate
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5. Using suitable diagram describe the cleansing action of soap and detergent.
6. Detergent is more effective than soap in hard water . Explain why.
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7. Complete the table below;
Additive in detergent Examples Function
Biological enzymes Amylase , proteases, cellulases and lipases
To remove protein stain such as blood
Builder
Filler Sodium sulphate, sodium silicate
Foam control agents To control foaming in detergent
Fragrances
Optical whitener
Suspension agent carboxymethylcellulose
Whitening agent
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B. FOOD ADDITIVES
1. Complete the table below:
Food additives Function Examples Antioxidants To prevent oxidation of food Ascobic acid, BHA, BHT,
tocopherol, sodium citrate
Flavourings To improve or restore taste of food
Food dyes Tatrazine , brilliant blue FCF
Preservatives
Stabilisers To prevent an emulsion from separating out
Thickeners
2. Complete the table below:
Antioxidant Example Function
Butylated hydroxyanisole (BHA) butylated hydroxytoluene (BHT)
Margarine To retard rancidity in oils
Ascobic acid (vitamin C)
Alpha tocopherol (vitamin E)
Sodium citrate
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3. Complete the table:
Flavouring Function Example
Monosodium glutamat (MSG)
To bring out the flavour in many food
Aspartame Diet drinks, low-calories frozen desserts and some soft drinks
Synthetic essences To produces artificial flavour which resemble natural flavours
4. Complete the table below:
Preservative Example How it works
Salt
Salted fish
Sugar
Vinegar
Sodium nitrite or sodium nitrate
Burger, sausage, launcheon meat
Slow down the growth of microorganismsBenzoic acid or sodium benzoate
Sulphur dioxide
5. what are the advantages and disadvantages of using food additives?
Advantages Disadvantages
make food stay fresh longer, look nicer and taste better
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C. MEDICINE
1. Traditional medicine are derived from plants and animals. Complete the table below:
Medicinal plant Function
Aloe vera (lidah buaya) To treat skin wound
Andrographis paniculata (hempedu bumi)
Eurycoma longifolia (tongkat ali)
Centella asiata (pegaga)
Ocimum basilicum(selasih)
Orthosiphon aristatus (misai kucing)
2. Give three examples of animals that are claim to have medicinal properties.
(i) …………………………………………(ii) …………………………………………(iii) …………………………………………
3. Modern medicine are made by……………………. in laboratories and are based on substances found in …………………
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4. Types of modern medicine: Complete the diagram below.
Chemistry Module 2009@ Hak Milik JPN Pahang
MODERN MEDICINE
Analgesic Psychotherapeutic medicine
Antibiotic
Examples:1.2.3.
Examples:1.2.
Stimulant Antidepressant Antipsychotic
Function: to relieve pain without causing numbness or affecting consciousness
Function:
Function: to reduce fatigue
Function: Function:
Examples:1.2.
Examples:1.2.3.
Examples:1.2.3.
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5. Complete the table below:
Type of Medicine /Example of Medicine Side effect
Traditional medicine
Analgesic :
Antibiotic
Antidepressant :
Stimulant Ussualy high doses or excessive use of stimulants over long periods of time can lead to anxiety, hallucinations, severe depression, or physical and psychological dependence
Antipsychotic
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6. Taking drugs excessively and without a doctor’s prescription is called ………………………..
7. Complete the table below:
Chemical Proper management
Detergent
Food additives
Medicines
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CHAPTER 5: CHEMICALS FOR CONSUMERS
B. Objective QuestionsKnowledge
1. The hydrolysis process of vegetable oil by alkali is called A Cracking B hydrationC Saponification D esterification
2. Which of the following is the base substance to make soap?
A. Oil B. Petroleum C. Sodium chloride D. Animal fats
3. Detergent is a salt that is produced from a reaction between A Acid and sulphonic acid B alkali and sulphonic acid C alkali and vegetable oil D acid and vegetable oil
4. Sodium chloride is added during the process of preparing soap to A dry the soap B remove excess alkali C reduce the solubility of soap in water D reduce the boiling point of soap solution
5. Figure 1 shows the structure of a soap ion.
COO-
Part X Part Y
FIGURE 1
Based on Figure 1, which of the following statements is true ?
A. Part X and Y are soluble in water. B. Part X and Y are soluble in grease. C. Part X is soluble in grease and part Y is soluble in water. D. Part X is soluble in water and part Y is soluble in grease.
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6. Figure 2 shows the structure of a detergent ion.
Figure 2
What are the parts labelledd P and Q respectively? P Q
A Hydrophylic hydrophobic B Hydrophobic Hydrophylic C Hydrophylic ion
D covalent Hydrophobic
7. Which of the following is the hydrophilic end of soap and detergent ions? Soap ion detergent ion
A -COO- -SO3-
B -SO3- -COO-
C CH3(CH2)14 -COO-
D -COO- CH3(CH2)14
8. Which of the following is the main function of soap?A Causes the precipitation of magnesium ions in waterB Changes hard water into soft waterC Reduces the surface tension of waterD Reduces the evaporation of water in the air
9. The information shows a part of the structural formula of a soap molecule.
CH3(CH2)14COO-
Which of the following is the name of the part ?
A Lauric B Glycerol C Palmitate D Alkylbenzene
10. Which of the following is true about soap or detergent ?
A Detergent forms scum in hard water B Soap forms scum in soft water C Scum decreases the effectiveness of the cleansing action of a soap D The presence of magnesium ions in detergent forms scum.
11. Which of the following statements is true about detergents?I can clean in hard waterII not biodegradableIII comprises of sodium sulphonic acid saltIV contains a hydrophylic end –SO3
-
A I and II onlyB II and v onlyC I,II, and III only
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D I ,II, III, and IV
12. Which of the following are the advantages of soap over detergent, as a cleansing agent?I soap is easily biodegradable II Soap can be used in hard waterIII Soap does not reduce the surface tension of waterIV Soap consist of a hydrocarbon region that dissolves all types of dirt
A I only C II and Iv onlyB I and III only D I, III and IV only
13. Which of the following can be found as additives in detergents?I drying agentII Biological enzymeIII Whitening agentIV Colouring
A II and III only C I,II ,III and IV B I,II and III only D II,III and IV only
14. The function of biological enzymes in detergent additives are to A whiten clothesB dry the detergentC perfume clothesD break down organic dirt
15. Which of the following is the function of benzoic acid , a food additives that is added to canned food?A thicken the liquidB preserves foodC makes the food tastierD prevents the oxidation of food
16. Which of the following matches of food additives and their functions are not correct? Food additives Function
A Monosodium glutamate makes the food tastierB ascorbic acid slows down the oxidation of foodC Sodium benzoate slows down the spoilage of foodD acacia gum Colours the food
17. Which of the following food additives can prevent the activity of microorganism in food?
A. Citric acid
B. Benzoic acid C. Ascorbic acid D. Triphenyl compound
18. Which of the following statements is true about antibiotics?A Obtained from animal cellsB Can kill virusesC A type of synthetic hormoneD Treats patients with disease caused by bacteria
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19. Streptomycin and penicillin are medicine that can be grouped asA AnalgesicsB Psychiatric medicineC AntibioticsD Hormone
20. Which of the following is the function of psychiatric medicine?A Reduces the feeling of painB Removes the feeling of anxietyC Treats patient with diseasea caused by bacteriaD Treats join diseases
21. Figure 3 shows the structural formula of a type of medicine that can relieve body aches and pain
Figure 3What is that medicine?A codeine C AspirinB Paracetamol D Streptomycin
22 What type of medicine that can relieve muscle and joint pains?A stimulant C aspirinB streptomycin D tranquiliser
23. Which of the following is the use of streptomycin, in the field of medicine?A Relieves painB Cures tuberculosisC Calms a patient down emotioanallyD Clots the blood at a wound
24. Which of the following matches modern medicine and its corresponding examples correctly? Modern medicine Examples
A Analgesic ParacetamolB Psychiatric StreptomycinC Antibiotic antidepressantD Analgesic Penicillin
25. Garlic can be used to treatA high blood pressureB skin diseaseC liver diseaseD exhaustion
26. Which medicine can relieve a headache?
A. Aspirin C. BarbiturateB. Cortisone D. streptomycin
27. Psychiatric patients are always restless and normally experience difficulties in sleeping. Which medicine is suitable to treat these patients ?
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A Aspirin B Codeine C Barbiturate D Streptomycin 28. Which of the following is the function of an analgesic ?
A To calm down the emotion of the patient B To treat asthma C To releive pain D To destroy bacteria
29. Which of the following pairs of types of modern medicine and their uses is true?
Types of Modern Medicine Uses of medicine
A
B
C
D
Antipsychotic medicine
Codeine
Streptomycine
Cortisone
To treat hallucination
To kill TB bacteria
To treat rheumatoid arthritis
To stop coughing
Understanding
30. A soap has the molecular formula as shown below.
CH3(CH2)14COO-Na+
What is the source of the soap?
A Coconut oil B PetroleumC Palm oil D Sunflower oil
31. A patient is experiencing difficulties in sleeping and is always feeling anxious. Which medicine is suitable to overcome the patients problems?A ParacetamolB penicillin C BarbiturateD Codeine
32. Figure 4 shows the structure of a soap ion
Figure 4
In what medium can part X and part Y dissolve in?Part X Part Y
A water greaseB grease oilC oil WaterD Water Water
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33. Detergents can wash effectively in hard water because detergent moleculesA dissolve in hard waterB ` dissociate in hard waterC reacts with calcium ion in hard waterD do not form precipitate
34. Figure 5 shows a soap ion
Figure 5
Which of the following statements are about the part of the soap ion that is labelled as P in figure 5?I Has covalent characteristicsII Consist of a hydrocarbon chainIII Breaks up the grease into small dropsIV Dissolves in dirt such as grease
A I and II onlyB I and III onlyC I,II and IV onlyD I,II,III and IV
Application
35. Figure 6 shows the cleansing action of soap.
Figure 6
Which of the following statement is true?A Part Y emulsifies the greaseB Part X reacts with waterC Part Y reacts with greaseD Part X will break off from part Y
37.
Figure 7Figure 7 shows a chemical equation that represents the reaction that occurs when preparingA aspirinB soap
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C sodium alkyl sulphate detergentD sodium alkyl benzene sulphonate detergent
38. A bowl of vegetable soup is found to be not very tasty.Which of the following food additives can be added to the soup?A StabiliserB FlavouringC AntioxidantD Colouring
39. Aspirin is not recommended for gastric patients becauce aspirinA contains alcoholB can cause addictionC can cause bleeding of the stomach wallD causes excess stomach enzymes to be secreted
40. The chemicals above are required for the preparation ofA paracetamolB aspirinC codeineD tranquilisers
C. Structure Questions
1. (a) In preparing soap, a strong alkali solution is added to fats. The mixture is heated and then sodium chloride is added. (i) Name one strong alkali used in preparing soap. …………………………………………………………………………
[1 mark] (ii) Why is sodium chloride added to the mixture?
…………………………………………………………………………[1 mark]
(b) The statement below is about soap and a detergent.
You have two socks stained with oil.
Describe briefly the experimental procedure, observations and conclusions to prove the above statement, by using substances such as soap, detergent and hard water.
Chemistry Module 2009@ Hak Milik JPN Pahang
The cleaning action of a detergent is more effective than soap in hard water.
Salicylic acid Concentrated sulphuric acid Ethanoic anhydride
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Procedure of the experiment:
………………………………………………………………………………...
.……………………………………………………………………………..…
………………………………………………………………………………...
………………………………………………………………………………...[3 marks]
Observations:
………………………………………………………………………………...
………………………………………………………………………………...[1 mark]
Conclusion:
………………………………………………………………………………...
………………………………………………………………………………...[1 mark]
(c) Analgesic and psychotherapeutic medicines are use to treat patients. Aspirin is an analgesic medicine and barbiturate is a psychotherapeutic medicine.
(i) What is the function of a barbiturate?
…..……………………………………………………………………………[1 mark]
(ii) Children are advised not to take aspirin because it causes bleeding of the intestine and stomach. Suggest one other medicine to replace the aspirin. …..…………………………………………………………………………...
[1 mark]
(iii) Figure 1 shows the structural formula of aspirin.
FIGURE 1
What is the molecular formula of aspirin?
….…………………………………………………………………………...[1 mark]
(iv) What is the molecular mass of aspirin?
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Use the information that the relative atomic mass of H = 1, C = 12 and O = 16.
………………………………………………………………………………[1 mark]
2. The following equation shows a reaction in the preparation of soap in a laboratory.
(a) What is the name of this reaction?
……………………………………………………………………………….[1 mark]
(b) (i) What is the homologous series of palm oil?
…………………………………………………………………………..[1 mark]
(ii) Complete the anion part of the soap particle in the space provided.
(c) A pupil wants to prepare a potassium palmitate soap. What alkali should he use?
…………………………………………………………………………………[1 mark]
(d) Figure 2.1 shows part of the washing action of detergent particles on a grease stained cloth.
FIGURE 2.1
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(i) State the part of a detergent particle that is soluble in grease.
……………………………………………………………………………[1 mark]
(ii) Based on Figure 2.1 explain the washing action of detergent particles on greasy stains.
……………………………………………………………………………
……………………………………………………………………………
…………………………………………………………………………… ……………………………………………………………………………
[3 marks]
(iii) Complete Figure 2.2 to show the condition of grease and detergent particles when the water is stirred.
[1 mark]
FIGURE 2.2
3. Table 1 shows the result of an experiment that was carried out to investigate the effectiveness of soap and detergent as a cleaning agent in hard water
Beaker W X Y Z Cleaning agent 500cm3 of soap
solution500 cm3 of soap solution + 200 cm3 of hard water.
500cm3 of detergent solution
500cm3 of detergent solution + 200 cm3 of hard water
Observation Foam is formed. The greasy cloth can be cleaned thoroughly.
No foam is formed. White precipitate appears on the surface of solution. Grease remains on the cloth
A thick foam is formed. The greasy cloth can be cleaned thoroughly
A thick foam is formed. The greasy cloth can be cleaned thoroughly
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a. i. What does it meant by hard water?
ii. How do you prepare a sample of hard water in the laboratory?
b. State all variables in this experiment i. Manipulated variable
ii. Responding variable
iii. Constant variable
c. What conclusion can be made from the results obtained?
d. If the experiment is repeated using hydrochloric acid to replace hard water , predict the results of the experiment.
4. (a) Diagram 1.1 shows a ginger plant. Ginger can be used as a traditional medicine.
Diagram 1.1
(i) Which of the parts P,Q,R or s, is used as the main source of medicine? Mark ( √ ) for your answer in the box provided in Diagram 1.1.
[1 mark] (ii) What illness can be cure by using ginger?
[1 mark]
(iii) How is ginger used to treat the illness in 1(a)(ii) ?
[1 mark] (b) Table 1.1 shows the functions of three type of medicines.
Function Type of medicinePrevent pain X:Kills or prevent the reproduction of bacteria
Y:
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Changes the emotions and behavior of the patient
Z:
Table 1.1
(i) Complete table 1.1 to show which medicines have the functions given in the table.[3 marks]
(ii) What is the side effect of medicine of type X if it is used by a child of less than 2 years old ?
………………………………………………………………………….[1 mark]
(iii) A patient treated by medicine of type Y must complete all the supply given by the doctor in order to make sure all the bacteria are killed.
What will happen if not all the bacteria are killed ?
…………………………………………………………………………..[1 mark]
(iv) Tranquilizer is an example of medicine of type Z.
Give one change that might happen to a patient’s emotions when treated using this medicine.
…………………………………………………………………………[1 mark]
5. (a) Diagram 1.1 shows an aloe vera plant.
(i) What illness can be cured by using aloe vera ?
(ii) Which part of the plant is used to treat the illness ?
(iii) Name one herbal medicine other than aloe vera and its function.
(b) Table 1 shows the examples of three types of modern medicine.
Type of medicine Examples Analgesics XAntibiotics YPsychoterapeutic medicine Z
Table 1
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(i) Complete table 1 by naming one example for each type of medicine.X: Y: Z:
(ii) State the function of analgesics
(iii) A patient should complete the full course of an antibiotic prescribed by the doctor. Explain briefly why?
(iv) State one side effect of taking psychoterapeutic medicine.
6. Diagram 2 shows five types of common food additives used in food processing industry.
i. State two functions of using food additives in food processing
ii. Name two natural food preservatives
iii. Name a natural colouring that makes food green in colour
iv. Name an artificial sweetener that can be used to replace sugar.
iv. Monosodium glutamate (MSG) is used in cooing primarily to enhance the flavour of food.
v. State two side effects of taking excess MSG over an extended period of time.
vi. Ascorbic acid is an antioxidant. What is the function of ascorbic acid when it is added to food?
vii. State an example of a thickener in the preparation of food.
7. A kind of jelly contains the following food additives :
a) State two reasons why food additives are added to the jelly.
b) Name a colouring that is added to the jelly
c) What is the colour that given by the colouring named inquestion above?
d) What is the function of benzoic acid?
e) Name a substance that can be used to replace pectin.
f) Name an antioxidant that is added to the jelly
Chemistry Module 2009@ Hak Milik JPN Pahang
Pectin,benzoic acid,ascorbic acid,tartrazine and octhyl ethanoate
Foodadditives
preservatives
Flavouring agents
Thickening agents
antioxidant
dyes
stabilisers
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g) Octhyl ethanoate gives the jelly orange flavour.
h) Name two chemicals needed to prepare octhyl ethanoatei) Name the reaction involved of octhyl ethanoate from the chemicals above?
D. Essay Questions
1. (a) State two methods of food preservation which are used in our daily lives and explain how the methods work.
[4 marks] (b)
[8 marks]
(c) A student carried out four experiments to investigate the cleansing effects of soap and detergent on oily stains in soft water and hard water. Table 1 shows the set-up of apparatus, types of water used, and the observation for Experiments I, II, III and IV.
TABLE 1
Compare the cleansing effects between28 | P a g e (i) Experiments I and II (ii) Experiments II and IV
Explain why there are differences in the observations. State the substance which is more suitable as a cleansing agent to remove oily stains
[8 marks]
2. Plan an experiment to investigate the effectiveness of soap and detergent as a cleaning agent in hard water. Your answer should consist of the following
(a) Problem statement(b) Hypothesis(c) All the variables involved(d) List of apparatus and materials
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A student discovered that his socks have oily stains. He washed them with soap.
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(e) Procedure of the experiment(f) tabulation of data
[17 marks]]
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