CHEMICALS FOR CONSUMERS

FORM 5 CHAPTER 5

By : Iskandar Zulqarnain Mohd Ishak (5B)

5.1 Soaps & Detergent

Soaps are sodium or potassium

salts of long-chain fatty acid.

General formula of a soap can be written as or

R is an alkyl group usually contains 12 or 18 carbons atoms. R can be saturated or unsaturated

PREPARATION OF SOAPS1. Soaps are prepared by the alkaline hydrolysis (saponification) of

vegetable oils and animal fats.

2. When oils or fats is boiled with concentrated sodium hydroxide solution, soap and glycerol are formed.

3. Sodium chloride is added to the soap mixture to cause precipitation of soap. The role of this NaCl is to reduce the solubility of soap in water.

DETERGENT• Detergents are made of synthetic cleansing

agents such as petroleum fractions. E.g. :

PREPARATION OF DETERGENTS(sulphonation)

The Cleansing Action of Soaps & Detergents•Both soaps and detergents have an ionic head and tail consisting of a long hydrocarbon chain.

•The ionic head is negatively-charged. It is hydrophilic which is soluble in water.

•The long hydrocarbon tail is hydrophobic which is soluble in oil but insoluble in water.

PROCESS OF CLEANSING

THE EFFECTIVENESS OF SOAPS & DETERGENTS

Soaps Detergents

Form scum (insoluble precipitate) in hard water. reduces amount of

soap for cleaning thus cause wastage

Does not form scum in hard water and also in acidic water. This means detergents are more effective than

soapBoth soaps and detergents do not form scum in soft water. Soft water is

water that contains little or no and . Hard water is vice verse.THE EFFECTIVENESS OF SOAPS IN ACIDIC WATER IS REDUCED

SOAPS

THE ADDITIVES IN DETERGENT

Amylases, proteases, lipase

Sodium tripolyphosphate

Fluorescent dyes

Sodium perborate

Cleaning agent

Soap Detergent

Effectiveness Effective cleaners in soft water

Effective cleaners in soft and hard water

Formation of scum

Yes No

Sources Natural resources (animals fats or vegetable oils)

Synthetic resources (petroleum fractions)

Formation of precipitate

Yes in acidic water No in acidic water

Effect on the environment

Biodegradable and not cause pollution

Non-biodegradable and gives thick foams that can kill aquatic lives

COMPARISON TABLE BETWEEN SOAPS & DETERGENTS

5.2 Food Additives

Preservatives Example How it worksSalt Salted fish Draws out water

Vinegar Pickled mango Provide acidic conditionSulphur dioxide Fruit juice Slow down growth of microorganisms

Some food additives can cause high blood pressure, heart attack, stroke, asthma, allergies and hyperactivity.

Antioxidants Example How it worksButylated hydroxyanisole (BHT) Margarine Retards rancidity in oils

Ascorbic acid (Vitamin C) Fruit juice Preserves color

Sodium citrate Cooked cured meat Stop fats turn rancid

Flavorings Example FunctionMonosodium glutamate (MSG) Frozen foods Bring out the flavor

Aspartame (non-sugar sweetener) Diet drinks Sweeten foods

Synthetic essences Pentyl ethanoate

(banana flavor)

Produces artificial flavors which resemble natural

flavors

5.3 Medicine• A medicine is used to prevent or cure a

disease or to relieve pain.• Medicines can be classified into traditional and

modern medicines.TRADITIONAL MEDICINES

Medicinal plant/animal Function

Aloe vera (lidah buaya) To treat skin woundsCentella asiatica (pegaga) To treat depressions and for longevity

Eurycoma longifolia (tongkat ali)

To increase the male libido

Sea cucumber (gamat) To treat Japanese encephalitis and hole in the heart

Ant To treat hepatitis B

modern MEDICINES

ASPIRIN PARACETAMOL CODEINE

for pain relief such as inflammation and dental

pain

Relieve mild to moderate pain such as headaches

and period pain

Used in headaches tablets and cough

medicines

Active ingredient is acetylsalicylic acid

Does not irritate stomach Most of it are synthesized from morphine

Can cause blood disorder and skin rashes if taken

for a long time

May cause drowsiness

Acidic. Cause brain damage. Never give to

children.

Overdosed paracetamol can lead to liver damage

Abuse of codeine may lead to addiction and

nausea

Penicillin Streptomycin

Extracted from the fungus, Penicillium notatum

Produced by soil bacteria,Streptomyces

To cure bacterial diseases such as tuberculosis (TB), whooping cough, pheumonia

Can be broken down by acid in stomach therefore usually given by injection

Side Effects of Antibiotics

Headache Allergic reaction

diarrhoea

Psychotherapeutic medicine

Function Example Side effects

Stimulant Reduce fatigue and elevate mood

Methylphenidate, amphetamine

High dose can cause hallucinations, anxiety

Antidepressant Reduce tension and anxiety

Tranquillisers Drowsiness, poor coordination. Overdosed intake cause sleeplessness

Barbiturates Cause addiction

Antipsychotic Treat psychiatric illness

Chlorpromazine, haloperidol

Drowsiness, rapid heartbeats

The Existence of Chemicals

Chemical Proper management Detergents • Use biodegradable detergents

• Wear gloves on strong detergents

Food additives

• Read the label to know what you eating

• Avoid rewarding children with junk food

Medicines • No self-medication• Follows doctor’s instruction• Do not overdose• Check for expiry date