PUNCAK CEMERLANG HOME TUITION BANDAR SRI DAMANSARA FORM 5 CHEMISTRY LESSON NO 31 CHEMICALS FOR CONSUMERS SOAP AND DETERGENT 1
Soaps are …………………………… or ……………………………….. salts of fatty acids .
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What are fatty acids ? ……………………………………………………………………………………………………………………………………………… ………………………………………………………………………………………………………………………………………………
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You are given the equation below : Fatty acid + Sodium Hydroxide
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Complete the following table below :
Fatty acid
Soap
Sodium salt of Fatty acid + Water ( ……………………… )
Formula of soap
C11H23COONa
Oil / fat used
C11H23COOH (Lauric acid )
Sodium laurate
C15H31COOH (Palmitic Acid )
Potassium …………………………….
Palm oil
C17H35COOH ( Stearic acid )
Sodium ………………………………
Animal Fats
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Coconut oil
Preparation of Soap a) Soap can be prepared from ……………………….. fats and ………………………………. Oils . b) Soap can be prepared by hydrolyzing fats / oils in ……………………………………………… or …………………………………………….. solution . c) This reaction is called …………………………………………………. d) The ………………………………………… process involves ……………………………. Fats / oils with ……………………………….. sodium hydroxide solution or ……………………………… hydroxide solution . The products are glycerol and the salts of fatty acids which are soaps . Complete the following :
+
3 Na OH
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Activity 1 Complete the sentences using the following words:
Surface tension, saponification, calcium, sodium, magnesium,potassium, sodium palmitate, sodium hydroxide, fat/oil ,potassium stearate, RCOO-Na +
1. Soap are…………………... or …………………….. salts of long-chain fatty acids. 2. General formula of a soap is……………………. or …………………………… 3. Examples of soap are …………………………….. and …………………………………….. 4. Soap cannot be used in hard water which contains the salt of...………………………. and .……………………………………… 5. The process of the production soap is known as ………………………… 6. The two materials used to prepare soap are ……………………………… and ……………………………………………… 7. When soap dissolved in water, it reduces the ……………………………….. of water.
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Activity 2 : Preparation of soap A. 50 cm3 of distilled water and two spatulas of table salts (sodium chloride) are added. B. 25 cm3 of concentrated sodium hydroxide solution is added in the same beaker
C. The mixture is boiled and stirred for a few minutes
D. The mixture is boiled slowly while being stirred with a glass rod for 15 minutes E. The observations are recorded in the table provided
F. The mixture in the beaker is left to cool down and the resulting white solid is filtered
G. The following tests are carried out on the white solid: a) Touched using a finger b) Some of the white solid is shaken together with water in a test tube. c) Tested with a red litmus paper. H. 5 cm3 of palm oil is poured into a beaker I. The white solid that is produced is washed with a little water and dried with the filter paper
1 Rearrange the methods for preparation of soap in the correct sequence. Then write your answers in the spaces provided. (i) 5 cm 3 of palm oil is poured into a beaker. (ii)
…………………………………………………………………………………………
(iii)
………………………………………………………………………………………..
(iv) ………………………………………………………………………………………….. (v) …………………………………………………………………………………………….. (vi) …………………………………………………………………………………………….. (vii) ……………………………………………………………………………………………
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1. Name another substance that can be used to replace sodium hydroxide,NaOH solution in the preparation of soap. …………………………………………………………………………………………… 2. Why was sodium choride, NaCl used in this activity? …………………………………………………………………………………………… 3. Write a word equation for the reaction between palm oil and sodium hydroxide. ………………………………………………………………………………………….. 4. Name two other substances that can be used to replace the palm oil in this activity. …………………………………………………………………………………………..
Detergents 1 2
Detergents are sodium or potassium salts of alkyl benzene sulphonic acid or alkyl sulphonic acid . Two common detergents are as follows :
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Cleansing action of soaps and detergents 1
The soap molecule or the detergent molecule has the following structure
Detergent molecule
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a) The circular part of the soap or detergent molecule is negatively charged and it is hydrophilic which attract water. b) The tail part is the long hydrocarbon chain of the soap and detergent molecule and has no charge. c) It is hydrophobic which repels water.
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The pictures below shows how the detergent / soap molecule removes the grease on the shirt. Soap / detergent molecule The soap molecules are spread out in the water Grease The hydrophobic tail of the dissolves d in the grease . The hydrophilic part of the soap molecule ( head ) dissolves in the water.
The shirt is now scrubbed . The grease starts to loosen and lift off from the surface of the shirt . Therefore, rubbing and scrubbing helps to speed up the loosening of the grease from the surface of the shirt.
The grease molecule is surrounded by the hydrophilic head and the grease is total lifted off from the surface of the shirt and suspended in water. The grease molecule is repelled from other grease molecules due to the negative charge on the hydrophilic head .
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ADDITIVES IN DETERGENTS
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Practice Questions Complete the sentences by using the words in the box below hydrophobic ,
emulsion,
surface tension, scrubbing
hydrophilic, small droplets ,
Soap /detergent reduces the ……………… of water. Hence water can wet the cloth thoroughly.
The …………………… part of the soap/detergent anion dissolves in grease.
The ……………….. part of the soap/detergent is attracted to the water molecules.
The ………………… action helps to lift off the grease from the cloth.
The grease is broken into ……………… during scrubbing. These droplets remain suspended and separated as an ……………….. due to the repulsion between the negative charges on the surface
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DIFFERENCES BETWEEN SOAP AND DETERGENT DEFINITION
EXAMPLES
SOAP ……………. or potassium salts of long-chain fatty acids. Sodium laurate CH3(CH2)10COONa, …………………….. palmitate, CH3(CH2)14COONa+
PREPARATION NAME OF METHOD
Saponification
MATERIALS
Palm oil, …………………….
CHEMICAL EQUATION
Chemical Equation :
(RCO)3(C3H5O3) (s) + 3NaOH) (aq) 3RCOONA (aq) + C3H5(OH)3 (aq)
From…………………… resources.
Animal fats examples cows and goats, vegetable oils –palm oil, olive oil and coconut oil.
SOURCES OF RAW MATERIAL
EFFECTIVENESS
Soaps are effective cleaners in soft water.
DETERGENT Sodium salt of..………………… acid
Sodium alkyl sulphate
Sodium alkyl benzene sulphonate.
Sulphonation
Concentrated sulphuric acid , long chain alcohol, sodium hydroxide.
Chemical Equation :
CH3(CH2)10 CH2-O-SO3H + NaOH CH3(CH2)10CH2-0-S-O3Na+ + H2O
Synthetic resources such as petroleum.
Effective cleaners in both soft and …………………. water.
FORMATION OF SCUM IN HARD WATER
Hard water contains calcium or magnesium ions. These ions react with soap to form an insoluble precipitate known as
Detergents do not form scum with hard water. They form soluble substances with calcium or …………………… ions.
……………………….. EFFECT TO ENVIRONMENT
Soaps are ………………….. and do not cause any pollution.
Detergents are ………………... Detergents give thick foam that kill aquatic lives
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Practice Questions Cleansing Action Of Soap And Detergent 1 The statement below is about soap and detergent. The cleaning action of a detergent is more effective than soap in hard water.
You have Zaki ‘s 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. Procedure of the experiment: ……………………………………………………………………………………….. ……………………………………………………………………………………….. ……………………………………………………………………………………….. ………………………………………………………………………………………. ………………………………………………………………………………………. Observations: ………………………………………………………………………………………. ………………………………………………………………………………………. Conclusions: ……………………………………………………………………………………… ………………………………………………………………………………………. 2
The following equation shows a reaction in the preparation of soap in a laboratory. Palm oil + Concentrated sodium hydroxide sodium palmitate(soap) + glycerol
boil
a) What is the name of this reaction? ……………………………………………………………………………… b) What is the homologous series of palm oil? …………………………………………………………………………….. c) Complete the anion part of the soap particle in the space provided
CH2 CH2 CH2 CH2 CH2 CH2 CH2 CH2 CH2 CH2 CH2 CH2 CH2 CH2 CH2
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C
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A pupil wants to prepare potassium palmitate soap. What alkali should he use? ……………………………………………………………………………………………….
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Figure 2.1 shows part of the washing action of detergent particle on grease stained cloth.
i)
State the part of a detergent particle that is soluble in grease. ……………………………………………………………………………………..
ii)
Based on figure 2.1 explain the washing action of detergent particles on greasy stains. …………………………………………………………………………………….. ……………………………………………………………………………………… ………………………………………………………………………………………
5 Soap and Shower Cream
a) Soaps are water-soluble sodium or potassium salts of fatty acids. Soaps are made from fats and oils, or their fatty acids, by treating them chemically with a strong alkali’ Quote from: The Soap and Detergent Association based in USA. Based on the quote and your knowledge of chemistry pick out the soap from the ingredients of the shower cream. Circle the correct answer. Ingredients: Deionised water
Sodium Lauryl Ether Sulphate
Sodium Cumene Sulphonate
Sodium Palmitate
Glycerol
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Write the correct captions for each stage.
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B .FOOD ADDITIVES 1. A food additive is a natural or synthetic substance which is added to food
to_________________
or ____________________its appearance, ________________ or ____________________ 2. Complete the chart. Types of additives
3. Complete the following table. Type of food additive.
State the function
Give two examples
To slow down the growth of microorganisms so that food can be kept for longer periods of time. To prevent oxidation that causes rancid fats and brown fruits
Salt, vinegar, benzoic acid.
Vitamins C and E
To improve the taste of food and restore taste loss due to processing. To prevent emulsion from separating out To thicken food To add or restore the color in food to enhance Its visual appeal. 4. What are the advantages and disadvantages of using food additives? ADVANTAGES
DISADVANTAGES
5. Figure 5.6 shows a part of the label of a tin of baked beans. a) State the food additives present in the food. Baked beans in tomato sauce Ingredients: Beans, sugar, tomato puree, salt and spice, permitted modified starch.
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b) To which type of food additives does each of the ingredients mentioned in (a) belong Food additives present in baked beans in tomato sauce
Type of food additives
6. Sugar is used as food preservative as well as for sweetening. Patients with medical conditions such as diabetes mellitus or obesity must be wary of their intake of sugar. a)
i) Name one artificial sweetener that can replace sugar. ……………………………………………………………………………………… ii)
Name one natural sweetener that can replace sugar. ………………………………………………………………………………………
b)
Artificial food colorings are used in some processed foods. Suggest two reasons for using food coloring.
…………………………………………………………………………………………….. ……………………………………………………………………………………………..
C: MEDICINE Learning Outcome You should be able to: • State examples of traditional medicines • State the types of modern medicines and their examples. • State the functions of each type of modern medicines • Describe the possible side effects of using modern and traditional medicines • Describe the correct usage of modern and traditional medicines.
ACTIVITY 9 Traditional medicines Complete the table below using the words in the box.
Lemon grass, lemon, garlic, aloe vera , ginseng , tongkat ali, ginger , quinine, Centella asiatica(pegaga), misai kucing, hempedu bumi,selasih, 16
Plant
Uses/function For preventing flu attack or asthma attack. For reducing high blood pressure. For treating stomach pain due to wind in stomach For supplying heat energy to keep the body warm. For treating itchy skin For treating burns on the skin. For treating boils or abscesses on the skin For preventing flu attack For treating skin diseases For treating malaria For preventing muscle cramps As tonic to improve the overall health of human beings For increasing energy, endurance and reducing fatigue Has antibacterial and antifungal properties For treating coughs As a tonic for after birth and general health To increase male libido To treat gout, diabetes and rheumatism To treat diarrhoe,fever and diabetes To treat coughs colds and bronchitis. To treat depression and for longevity
Activity 10
: Modern Medicines
Complete the table below for classification of modern medicines and its function. (Please refer to page 198 – 201 from your text book) Type of modern drugs a) Analgesic
b) ……………………..
Examples
Uses
•Aspirin
To relieve pain
•Paracetamol
.………………………………
•Codeine
To treat headache and cough
•Penicillin
To cure bacterial diseases such as tuberculosis (TB) and pneumonia.
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Streptomycin
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…………………………………
Psychotherapeutic drugs
• Stimulants : examples amphetamine, dextroamphetamine methylphenidate
To reduce fatigue and elevate mood.
• Antidepressant :examples tranquilizers,
To calm down a person and reduce tension and anxiety
• barbiturates
………………………………..
• Antipsychotic
………………………………..
Activity 11 : Modern Medicines and Its Side Effects State one side effect for the following drugs Type of modern drug Side effect Aspirin Paracetamol Codeine Penicillin Streptomycin Amphetamine Activity 12 Answer the following questions. 1. Codeine, insulin, streptomycin and tranquilizer are examples of modern medicine. Which of the examples is used to a) Treat diabetes mellitus? …………………………………………………………………………………. b) Treat pneumonia …………………………………………………………………………………. c) Calm down the patient. …………………………………………………………………………………. d) Relieve headache. …………………………………………………………………………………. 2. Antibiotic is a group of medicine used to kill and prevent the growth of bacteria. a) Name a disease that can be treated by antibiotic. ………………………………………………………………………………….. b) State two examples of antibiotic …………………………………………………………………………………..
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c) Describe a good practice of taking antibiotic. …………………………………………………………………………………. d) Explain your answer in ( c ) ………………………………………………………………………………….. 3. Aspirin is an example of analgesic. a) What is an analgesic? …………………………………………………………………………………… b) Normally aspirin is not prescribed to two groups of patient. Name the groups. …………………………………………………………………………………… c) Explain your answer in (b) …………………………………………………………………………………… d) Give another example of analgesic. …………………………………………………………………………………… 4. What is the use of insulin? ………………………………………………………………………………….. 5. State two differences between traditional medicines and modern medicines. …………………………………………………………………………………… …………………………………………………………………………………… 6. Penicillin and streptomycin are the examples of antibiotics. a)
What is the function of an antibiotic?
…………………………………………………………………………………… b) Why are penicillin and streptomycin given by injection and not taken orally? ……………………………………………………………………………………. Activity 13 1. Psychotherapeutic medicines can be classified into stimulant, antidepressant and antipsychotic. For each group in the classification, a) State its function b) Give one example c) Give one side effect. Psychotherapeutic medicines
Function
Example
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Side effect
Stimulant
Antidepressant
antipsychotic
2. Suggest one proper way to manage each of the following chemicals. Chemicals Detergent
Proper management
Food additives Medicines
3. Figure 3.1 shows a part of the label of a tin of sardines. Taiping sardines Ingredients: Fish, tomato sauce, salt, xanthan gum. Figure 3.1 List all the food additives used in the sardines. ……………………………………………………………………………………………… ……………………………………………………………………………………………… ……………………………………………………………………………………………… 4. To which type of food additives does each of the ingredients mentioned in (a) belong? ………………………………………………………………………………………………. ………………………………………………………………………………………………. Activity 14 1 a) Diagram 1.1 shows a ginger plant. Ginger can be used as a traditional medicine.
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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 ii) What illness can be cured by using ginger? ………………………………………………………………………………………
iii) How is ginger used to treat the illness in 1 (a) (ii)? ………………………………………………………………………………………
b)
Table 1.1 shows the functions of three types of medicine. Functions
Type of medicine
Prevents pain
X: ……………………………….
Kills or prevents the reproduction of bacteria.
Y…………………………………
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.
ii) What is the side effect of medicine of type X if it is used by a child of less than 2
years?
……………………………………………………………………………………………….. 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.
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What will happen if not all the bacteria is killed? ……………………………………………………………………………………………………. 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. …………………………………………………………………………………………………….
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