Embed Size (px)
Citation preview
1
CHAPTER 5
2
CHEMICAL FOR CONSUMERSCHEMICAL FOR CONSUMERS
A.A. Soap and DetergentSoap and Detergent
B.B. Food AdditivesFood Additives
C.C. MedicineMedicine
D.D. The Existence of ChemicalsThe Existence of Chemicals
3
(A)
4
Learning OutcomesLearning Outcomes1. State what soap is
2. State what detergent is
3. Describe soap preparation process
4. Describe detergent preparation process
5. Describe the cleansing action of soap
6. Describe the cleansing action of detergent
7. Compare and contrast the effectiveness of cleansing action of soap and detergent
8. Identify the additives in detergent and their respective functions
5
What is soap?What is soap?• Soaps are sodium or potassium salts of long-
chain fatty acids.
• General formula of a soap can be written as: RCOONa+ or RCOOK+
• R is an alkyl group that usually containing 12 to 18 carbon atoms. R can be saturated or unsaturated
• Soaps are prepared through saponification
6
Formula of soap
7
SaponificationSaponification• Saponification is a process to prepare soap.
• Soap is made by boiling a mixture of fats or vegetable oil with concentrated alkali (NaOH or KOH)
8
What is detergent?What is detergent?• Detergent is non-soap cleansing agent. • Detergent is the sodium salt of sulphonic acid
• It is divided into natural detergent and synthetic detergent
• Natural detergent is made from animal or vegetable oil while synthetic detergent is normally made from petroleum
• Commercialized detergent are usually sodium alkyl sulphate and sodium alkyl benzene sulphonate
9
Formula of detergent
10
11
Comparison of Soap and Detergent
Soap Detergent
Strength
Biodegradable Not poisonous to
aquatic life
effective in hard water and acidic water
Weakness Not effective in hard
water and acidic water
not biodegradable
12
The cleansing action of soap and detergent
• The cleansing action of soap and detergents results from their ability to lower the surface tension of water.
• This ability is due to the structure of soaps and detergents.
13
The structure of soaps and detergent
14
The structure of soaps and detergent
Soluble in oils or grease
Soluble in water
15
Cleansing Action of Soap and DetergentCleansing Action of Soap and Detergent
1. Soap reduces the surface tension of water.
2. This increase the wetting ability of water.
3. So, the surface of cloth is wetted thoroughly.
16
1. The hydrophobic part of the soap anion dissolves in the grease.
2. The hydrophilic part attracted to the water molecules.
17
1. Scrubbing helps pull the grease free from cloth surface.
18
1. Grease is removed from the cloth surface as tiny oil droplets.
2. Tiny oil droplets with negative charge repel each other.
3. This prevent them from redeposit on the surface.
19
20
21
Cleansing Action of Soap and DetergentCleansing Action of Soap and Detergent
Aim : To compare and contrast the effectiveness of cleaning action of soap & detergentApparatus : 250cm3 beakers, 100cm3 measuring cylinder, glass rodMaterial : detergent & soap solution , soft water, hard water ( distilled water + MgSO4 ), pieces of cloth (2cm x 2cm) with oily stain
22
Procedures:1. Prepare 4 beakers with the content below:
2. Stir the solution in each beaker using a glass rod until no changes can be observed
3. Record all changes that occurred4. Place a piece of cloth with oily stain into each beaker.5. Wash the oily stain on each piece using the solution in each
beaker and stirred6. Observe and record whether the oily stain on each piece of
cloth dissapear.
Exp Content
I 100cm3 of soap solution
II 50cm3 of soap solution + 50cm3
MgSO4
III 100cm3 of detergent solution
IV 50cm3 of detergent solution + 50cm3
MgSO4
23
Result:
Conclusion: Soap solution was an effective cleansing agent in soft
water but not in hard water. Detergent solution was effective in both solution.
Exp Observation
I A lot of lather was formed. The oily stain was removed. The cloth was clean
II No lather but white precipitate was formed. The oily stain remained on the cloth.
III A lot of lather was formed. The oily stain was removed. The cloth was clean
IV A lot of lather was formed. The oily stain was removed. The cloth was clean
24
Additives in detergent
Additives Function
biological enzymes To remove protein stains such as blood
fragrances To add fragrance to both the detergent and fabrics
whitening agents To convert stains into colourless substances
suspension agents To prevent the dirt particles removed from redepositing onto cleaned fabrics
foam control agents To control foaming in detergent
builder To enhance the cleaning efficiency of detergent by softening the water
25
(B)
FOOD ADDITIVES
26
FOOD ADDITIVES
• A natural or synthetic substance which is added to food to prevent spoilage or to improve its appearance, taste or texture
27
Types of food additives
1.1. PreservativesPreservatives
2.2. AntioxidantsAntioxidants
3.3. Flavouring agentsFlavouring agents
4.4. StabilizersStabilizers
5.5. Thickening agentsThickening agents
6.6. DyesDyes
28
PreservativesPreservatives
Are substances added into food to slow down or prevent the growth of microorganism such as bacteria, fungi or microorganisms.
Food can be kept longer.
29
Examples of PreservativesExamples of Preservatives
PreservativesSodium nitrite,
NaNO2
Functionto preserve and stabilize the red colour in meats.
Found infrozen meat, canned meat, sausages and burger
Negative effect
Cause stomach cancer because the nitrites produces carcinogenic nitrosamines
30
Examples of PreservativesExamples of Preservatives
Preservatives
Benzoic acid, C6H5COOH
Sodium benzoate, C6H5COONa
Functionto prevent the growth of bacteria
Found inFruit juice, chili sauce, tomato sauce, oyster sauce, soy sauce
Negative effect
Usage in great amount will damage the nervous system.
Allergic to some people
31
Others Preservatives
Preservatives Function and Examples
Salt
Draws out water from the cells of microorganism and retards the growth.
Found in salted fish, salted eggs, salted vegetables, ham and bacon
32
Others Preservatives
Preservatives Function and Examples
SugarDraws out water from the cells of microorganism and retards the growth.
Found in jelly, fruit jams and pickles fruit.
33
Others Preservatives
Preservatives Function and Examples
VinegarProvide acidic medium that prevent the growth of microorganism
Found in pickled fruits, chili and vegetables
34
Others Preservatives
Preservatives Function and Examples
Sulphur dioxidePrevent the growth of microorganism
Found in soft drinks and sauces.
35
Antioxidants
Antioxidants are added to prevent oxidation of
fats and oils.
Oxidation of fats and oils in food cause it to
become rancid.
Oxidation of fruits causes brown fruits.
36
• Examples :
» ascorbic acid (vitamin C)» tocopherol (vitamin E)» sodium citrate» butylated hydroxyanisole (BHA)
» butylated hydroxytoluene (BHT)
37
Examples of food contains Antioxidants
Food contains antioxidants are :
cakes, biscuits, margarine, deep fried food, vegetable oil.
38
Flavourings
flavourings are used to improve the taste of food
and restore taste loss because of processing.
39
• Examples of flavourings are
• sugar, salt, vinegar, • Monosodium Glutamate (MSG) ,• Aspartame, • synthetic essences mostly ester
Examples :
- pentyl ethanoate (banana flavour) - ethyl butanoate (pineapples flavour) - octyl ethanoate ( orange flavour)
40
Stabilizers
Stabilizers helps to prevent an emulsion from separating out.
Examples of stabilizer are
Lecithin,
Mono-glyceride of fatty acids
Di-glyceride of fatty acids
41
Stabilizers Stabilizers are used in margarine, butter, ice
cream and salad cream (mayonnaise, thousand island etc)
42
Thickeners
Thickeners are often added to food to alter the texture of food (thicken foods)
Examples
Starch - used in instant soup and puddings
Pectin - used in making of jams and jelly
Acacia gum - used to thicken chewing gum, jelly and wine
Gelatine – used in yogurt
43
Food Dyes
Food Colouring are dyes.Food Colouring are dyes.
Food dyes are used to add or restore the colour Food dyes are used to add or restore the colour in food due to food processing.in food due to food processing.
Food Dyes are normally azo compounds or Food Dyes are normally azo compounds or triphenyl compoundstriphenyl compounds
44
Tartrazine a yellow dyes from azo compound
used in orange drinks, custard powder, sweets and apricot jam
Is believed to cause hyperactivity in children
Brilliant Blue FCF blue triphenyl dye
used in sweets
Anthocyanin Found naturally in red grapes, red cabbages and sweet potatoe
contains antioxidant properties
Examples of Food Dyes
45
Effect of Food Additives on Health
Food Additives Harmful Effects
Sodium nitrite Can cause cancer
Sodium benzoateAffect nerve function
Cause allergy
TartrazineCan worsen the condition of asthma patients
Cause hyperactivity in children
Colouring substance eg.Amaranth, sunset yellow, ponceau 4R
Cause cancer, migraine, allergy and deformity of babies
Monosodium Glutamate
Cause health problem form long term used like headaches, difficulties in breathing, vomiting
46
47
Medicines
Can be classified as
1. Traditional Medicines
2. Modern Medicines
48
•
Medicines
Traditional Medicine Modern Medicine
Aloe VeraCentella Asiatica
(Pegaga)
Eurycoma Longifolia(Tongkat Ali)
Orthosiphon Aristatus(Misai Kucing)
Analgesics
Antibiotics
Andrographis Paniculata(hempedu bumi)
Ocimum basilicum(Selasih)
Psychotherapeutics
Cocaine Quinine
Ginger
Garlic
Mint(Pudina)
Lemon/ Oranges
49
50
Aloe Vera(lidah buaya)
to treat skin wounds
Centella Asiatica(Pegaga)
to treat depression & for longevity(longlife
51
Eurycoma Longifolia(Tongkat ali)
to increase the male libido(nafsu)
Orthosiphon Aristatus(Misai kucing)
to treat gout, diabetes and rheumatism
(sakit sendi/tulang)
52
Andrographis Paniculatahempedu bumi
to treat diarrhoea, fever and diabetes
Ocimum basilicumSelasih
to treat coughs, colds and bronchitis
53
Coca plantto produce
cocaine(drug) as pain killer
Quinine from Cinchona plant
to cure Malaria
54
Ginger (halia)for stomach pain due to
wind in stomachfor keeping body warm
for preventing flu attack
Mint (pudina)to increase body temperature
for sweating
55
Garlicfor preventing flu attack
or asthma attackfor reducing high blood
pressure
Lemon/orangefor preventing flu attack
for treating skin diseases
56
Kacip Fatimahleaf decoction drunk for
dysentery(intestinal infection)
Lemon grasspound leaf apply to forehead for curing
headache
57
Modern Medicines
• Classified into 3 main group
1. Analgesics
2. Antibiotics
3. Psychotherapeutics
58
Analgesics• Medicines to relieve pain.
Examples of analgesics
AspirinTo relieve pain
& anti-inflammatory
ParacetamolReduce fever & relieve pain
CodeineRelieve minor to moderate pain
59
60
Antibiotics
• Medicines that destroy or prevent the growth of microorganism
Examples of antibiotics
Penicilin to treat pneumonia,
gonorrhoea & syphilisStreptomycin
To treat tuberculosis(TB)
61
62
Psychotherapeutic
• For treating mental or emotional illness.
• Can be divided into 3 main group:
– STIMULANTS– ANTIDPRESSANT– ANTIPSYCHOTIC AGENTS
63
Psychotherapeutic Psychotherapeutic MedicinesMedicines
StimulantsDrugs that stimulate the activity of brain
& central nervous system
AntidepressantMedicines that reduce Tension and anxiety
Antipsychotic AgentHelp a person to
live a more normal life
ExamplesCaffeine
amphetamines
Examplesprozac
Exampleschloropromazin
64
65
Side Effects of Modern Medicines
Medicines Side Effects
aspirin
Can cause bleeding in the stomach because it is very acidicCan cause allergic reactions, skin rashes & asthmatic attacks
penicillinCan cause allergic reaction which may be fatal
amphetamines
People abuse amphetamines are excitable & talkativePsychologically addictive & can cause heart attackCan cause anxiety, sleeplessness, aggressive behaviour and decrease appetite
codeine Cause addiction
66
Side Effects of Modern Medicines
Medicines Side Effects
streptomycin
Cause nausea, vomiting, dizziness, rashes & feverCause loss of hearing following long-term use
stimulants Can cause addiction
antidepressants
Can cause addictionCan cause headaches, grogginess & loss of appetite
Antipsychotic drugs
Can cause dry mouth, blurred vision, urinary retention, constipationCan cause tremor and restlessnessSedation (make people calmer or sleepy)
