Chapter 5

CHEMICALS

FOR

CONSUMERS

2

Soap and Detergent Food Additive

Medicine

1. Define the soap 2. Define the detergent 3. Explain how the soap reacted in a

cleaning process? 4. Define the hard water 5. Explain why detergent more effective

than soap when cleaning using the hard water?

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. 4. List 2 example of medicine for each

type of the medicine respectively. 5. Gives three example of traditional

medicine and their usage.

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A. SOAP AND DETERGENT 1. Definition

(i) Soap : A sodium or potassium salt of long-chain .

General formula of soap:

or

(ii) Detergent : A sodium or potassium salt of acids or .. acid.

General formula of detergent:

Sodium alkyl sulphate Sodium alkylbenzene sulphonate

2. Soap preparation process

Soap is prepared by hydrolyzing 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: + 3NaOH +

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PREPARATION A SOAP IN LAB Describe how soap can be prepared in laboratory

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3. Detergent preparation process During the preparation of detergent, 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 detergent

5. Structure of Soap and Detergent The molecular structure of soap/detergent can be divided into two parts: a. . part Soluble in water but insoluble in oil

b. ... part Insoluble in water but soluble in oil

A sodium alkyl sulphate A sodium alkylbenzene sulphonate

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6. Using suitable diagram describe the cleaning action of soap and detergent

7. Comparison of Cleaning Action of Soaps and Detergents.

Washing Agents Soaps Detergents

Effectives

Q: Detergent is more effective than soap in hard water. Explain why.

Formation of scum

Source

Formation of compounds

Effect on the environment

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8. Complete the table below.

Additive in detergent Examples Function

Biological enzyme Amylase, proteases, cellulose and lipases

To remove protein stain such as blood

Builder

Filler Sodium sulphate, sodium silicate

Foam control agent To control foaming in detergent

Fragrance

Optical whitener

Suspension agent Carboxymethylcellulose

Whitening agent

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B. FOOD ADDITIVE 1. Food additives

Complete the table below:

Food additives Function Examples

Antioxidant To prevent oxidation of food Ascorbic acid, BHA, BHT, tocopheral, sodium citrate

Flavourings To improve or restore taste of food

Food dyes Tatrazine, brilliant blue FCF

Preservatives

Stabilizers To prevent an emulsion from separating out

Thickeners

2. Preservatives

Complete the table below:

Preservative Example How it works

Salt Salted fish

Sugar

Vinegar

Sodium nitrate or sodium nitrate

Burger, sausage, launcheon meat

Slow down the growth of microorganism Benzoic acid or sodium benzoate

Sulphur dioxide

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3. Antioxidant Complete the table below:

Antioxidant Example Function

Butylated hydroxyanisole (BHA) Butylated hydroxytoluene (BHT)

Margarine To retard rancidity in oils

Ascorbic acid (Vitamin C)

Alpha tocopheral (Vitamin E)

Sodium citrate

4. Flavourings

Complete the table:

Food additives Function Examples

Monosodium glutamate (MSG)

To bring out the flavor in many food

Aspartame Diet drink, low-calories frozen desserts and some soft drinks

Synthetic essences To produce artificial flavor which resemble natural flavours

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 medicines 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:

TYPES OF MODERN MEDICINES

Psychotherapeutic medicine

Function: Function:

Common analgesics:

Function: Function: Function:

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5. Complete the table below:

Type of medicine / example of medicine Side effect

Traditional medicine

Analgesic

Antibiotic

Antidepressant

Stimulant

Usually 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