CHEMISTRY IN EVERY DAY LIFE

CHEMICALS IN MEDICINE AND HEALTH CARE

 

Chemotherapy 

 

Chemical substances of natural or synthetic origin which are used for curing diseases and reducing suffering from pain are called medicines or drugs. The branch of science which deals with the treatment of diseases using suitable chemicals is known as chemotherapy. 

 

DRUGS AND MEDICINES

 

A medicine is a chemical substance which cure the disease is safe to use has negligible toxicity and does not cause addiction. In contrast, a drug is a chemical substance which also cures the diseases but habit forming causes addiction and serious side effects. 

 

Classification of medicines 

 

Medicines are generally classified according to the purpose for which they are used. The different terms thus used along with examples are given below: 

 

Analgesics: Medicines used for getting relief from pain are called analgesics. 

 

These are of two types: 

 

(i) Narcotics and (ii) Non – narcotics 

 

(i) Narcotics: Drugs which produce sleep and unconsciousness are called narcotics.
e.g. Morphine, codeine, marijuana etc. 

(ii) Non-narcotics: Aspirin (2 acetoxybenzoic acid) is the most commonly used analgesic with antipyretic (temperature lowering) properties.

 

Now a days because of its antiblood clotting action, aspirin is widely used to prevent heart attacks. Other examples are Ibuprofen, Naproxen etc.  

Tranquillizers or Hypnotics

 

The drugs which act on the central nervous systems (CNS) and help in reducing stress and fatigue by inducing a sense of well being are called tranquillizers. 

The most commonly used tranquillizers are barbituric acid and its 5, 5 – disubstituted derivatives such as veronal, luminal, seconal amytal and membutal. 

 

Cleordiazepoxide and meprobante are relatively mild tranquillizers and hence are used for reliveing tension. Equanil is used for reducing depression and hypertension. 

 

Reserpine isolated from the Indian plant Rauwolfia serpentine is also a powerful tranquillizer. It also slows down the pulse rate and lowers the blood pressure. 

 

Antiseptics and Disinfectants 

 

(A) Antiseptics 

 

Antiseptics are the chemicals substances which prevent the growth of micro – organisms and may even kill them. 

 

(B) Disinfectants 

 

Disinfectants are chemical substances which kill micro – organisms but are not safe to be applied to the living tissues. They are generally used to kill the micro – organisms present in drains, toilets, floors etc. 

 

A few examples of disinfectants and antiseptics used in every day life are given below: 

 

(a) Chlorine: A low concentration of chlorine i.e. 0.2 to 0.4 parts per million (ppm) is used for sterilization of water to make it fit for drinking purposes. 

 

(b) Dettol: Antiseptic is a mixture of chloroxylenol and Tripineol or in a suitable solvent. 

 

(c) Bithional: Bithional is added to good quality soaps to reduce the odours produced by bacterial decomposition of organic matter on the skin. 

 

(d) Iodine: Iodine is a powerful antiseptic, it is used as tincture of iodine (which is 2-3% solution of iodine in alcohol and water). 

 

(e) Iodoform (CHI3): Which produces iodine on coming in contact with skin is used as antiseptic powder for wounds. 

 

(f) Dyes: Some organic dyes are effective antiseptics and are used for treatment of infectious disease. For example two well known antiseptic dyes are gention violet and methlyene blue. 

 

Boric acid

 

Boric acid in the form of dilute aqueous solution is a mild antiseptic and used for eye wash. It also forms part of antiseptic baby powders. 

Hydrogen peroxide 

 

Hydrogen peroxide is also used as an antiseptic under the name perhydrol for washing wounds, teeth and ears. 

 

Salol (Phenyl salicylate) 

 

Salol is used as an intestinal antiseptic for throat ailments. 

 

Mercurochrome solution (2 – 5%) 

 

Mercurochrome solution is used as an antiseptic for skin, mucous surfaces and wounds. 

 

Cresols (Lysol) 

 

A solution of cresols (i.e. m and p – methyl phenols) in soapy water in called lysol and is used as disinfectant. 

Antimicrobials 

 

Drugs used to cure diseases caused by microbes or micro organism such as bacteria, viruses, fungi etc are called antimicrobials. These include antibacterial, antifungal and antiviral agents. 

 

Control of microbial diseases

 

All the microbial diseases are controlled by the following three methods: 

 

(a) By using the bactericidal drug, i.e. a drug which kill the organisms in the body. 

(b) By using the bacteriostatic drugs i.e. a drug which inhibits or arrests the growth of the organism. 

(c) By increasing the immunity and resistance of the body of infection. 

 

Some important antimicrobial drugs are: 

(i) Antibiotics (ii) sulpha drugs

 

Antibiotics 

 

Antibiotics are now defined as chemical substances (produced wholly or partially by chemical synthesis), which in low concentration, either kill or inhibit the growth of micro organisms by intervening in their metabolic processes. 

For example: (i) firetantibiotic, penicillin (ii) Chrysogenum 

Types of antibiotics 

 

The antibiotics can be either bacterial or bacteriostatic.

 

Bactericidal Bacteriostatic 

Penicillin Erythromycin 

Aminoglycosiders Tetracydine 

Ofloxacin Chlroamphenicol

 

Broad spectrum antibiotics 

 

The full range of micro organisms attacked by an antibiotic is called its spectrum. Broad spectrum antibiotics are effective against several different types of harmful bacteria. 

 

For example: Tetracyline, Vancomycin and ofloxacin and a mixture of potent antibiotics chloramphenicol. 

 

Sulpha Drugs 

 

A group of drugs which are derivatives of sulphanilamide are called sulpha drugs. 

 

Sulphadiazine

Sulphapyridine

 

Sulphaguanidine

 

These have great antibacterial powers and have been widely used against diseases (such as diphtheria, dysentery, tuberculosis etc) caused by CoCCi infections, ⎯streptococci, gonococci and pneumo-cocci. 

Example: (i) Sulphanilamide 

(ii)Sulphadiazine 

(iii) Sulphapyridine 

(iv) Sulphaguanidine 

 

Antihistamines 

 

These drugs are also anti allergic drugs since they are used to treat allergy i.e. skin rashes, inflammation of tissues, asthma (Breathing difficulties) and itching of hives. Science allergy is caused due to release of histamine in the body, therefore these drugs are also called antihistamines. Example: Diphenythydramine, cetrizine, chlorpheniramine, promethanzine etc. 

 

Antacids 

 

Substance which neutralize the acid and raise the pH to an appropriate level in stomach are called antacids. 

 

The most commonly used antacids are: magnesium hydroxide, magnesium carbonate, magnesium trisilicate, aluminium hydroxide gel, sodium bicarbonate and aluminium phosphate. 

 

DYES 

 

A dye is a coloured substance, which can be applied in solution or dispersion to a substance such as textile fibres (cotton, wool, silk, polyester, nylon) paper, leather, hairs fur, plastic materials, wax, a cosmetic base, giving it a coloured appearance. 

 

1. Conditions which a dye must satisfy

 

A substance can be used as dye for the textiles only if it satisfies the following conditions: 

 

(i) It must have a suitable colour. 

(ii) It must be able to fix itself or capable of being fixed to the fabric from the solution. 

(iii) When fixed, it must be fast to light resistant to the action of water, soap detergents etc. During washing or to the organic solvents during dry cleaning etc. 

 

2. Classification of dyes 

 

Dyes are classified either according to their constitution or method of application. The classification can be done as: 

(a) Classification based on constitution 

 

This classification is based on the distinguishing structural units present in the dye. 

 

(b) Classification based on application 

Depending upon the process of application the dyes are classified as: 

(i) Acid dyes (ii) Basic dye (iii) direct dyes (iv) disperse dyes (v) Fibre reactive dyes 

(vi) Insoluble azo dyes (vii) Vat dyes (viii) Mordant dyes 

(i) Acid dyes 

 

The sodium salts of azo dyes containing sulphonic acid (⎯SO3H) and carboxylic acid (⎯CO2H) groups are called acid dyes. 

 

These do not have affinity for cotton and hence can not be used to dye cotton. Typical examples of acid dyes are orange – I, Orange – II, methyl organe, methyl red and congo red. 

 

(ii) Basic dyes 

 

These dyes are the salt of the coloured bases containing amino groups (⎯NH2 or ⎯NR2) as auxochromes. These include azo and triphenyl methane dyes. Some common examples of this class are aniline yellow, butter yellow, chysodine G and malachite green. 

 

(iii) Direct dyes 

 

These are water soluble dyes. As the name suggests, these are those dyes which can be directly applied to the fabric from an aqueous solution. These are most suitable for fabric which can form hydrogen bonds with the dyes. 

 

Thus these are usually used for dying cotton, wool, silk, rayon and nylon. Example: congored and martius yellow. 

 

(iv) Disperse dyes

 

These are water insoluble dyes and are applied to the fabric in form of a dispersion of the finely divided dye in a soap solution in the presence of some stabilizing agent such as phenol, cresol or benzoic acid. 

 

Example: (i) Celliton fast pink B and 

(ii) Celliton fast blue B. 

 

(v) Fibre reactive dyes 

 

These are those dyes which contain a reactive group. Which combines directly with the hydroxyl or the amino group of the fibre, because of the formation of permanent chemical bonds between the fibre and the dye, the colour of the dyed fabric is fast and has a long life. Dyes which are derivatives of 2, 4 – dichloro-1, 3, 5 – triazine are important examples of fibre reactive dyes. 

 

(vi) Ingrain dyes or Insoluble azodyes

 

These are obtained by coupling of phenols, naphthols arylamines, amio-phenols adsorbed on the surface of a fabric with a diazonium salt. As there is only surface absorption of the dye on the fabric, the colour is not fast. Example: para red, nitroaniline red. 

 

(vii) Vat dyes 

 

Vat dyes are insoluble in water and hence can not be used directly for dying. Therefore, they are first reduced to a soluble colourless in large vats with a reducing from (leucoform) agent. Such as an alkaline solution of sodium hydrosulphite. Under these alkaline conditions, the leucoform develops affinity for cellulose fibres. Therefore, these dyes are mainly used to dye cotton fibres. 

Examples: Indigosol O. 

(viii) Moradant dyes 

 

These dyes are primarily used for dying of wool in the presence of metal ions. The metal ion binds to the febric and the febric and the dye acting as ligand coordinates to the metal ions. The same dyes in the presence of different metal ions impart different colours to the fabrics. Alizarin imparts rose red, blue, brownish red, violet and red colour to the fabric in the presence of Al3+, Ba2+, Cr3+, Mg2+ and Sr2+ ions respectively. 

 

COSMETICS 

 

The word cosmetics is derived from Greek word kosmetikos. It means decorating or beautifying or improving complexion of skin. Some of the cosmetics which find use in daily life are discussed below 

 

1. Creams 

 

Creams are used for facial make – up. These are often classified as: 

Clearing creams, cold creams, vanishing cream, sunburn creams and bleach creams. 

 

(a) Cleansing creams: Remove facial make up, surface grime, lipstick and oil. 

(b) Cold creams: Lubricate the skin and prevent roughness and chaffing. 

(c) Vanishing creams: Keep the skin cool and oily. 

(d) Sun burn creams: Save the skin form sun burn in summer. 

(e) Bleach creams: Exert a bleaching effect on dark skin. 

 

2. Perfumes 

 

Perfumes are the materials used to provide fragrance. Several requirements have to be fulfilled to make a good perfume and any material, which just gives good smell, may not be a perfume. 

A perfume invariably consists of three ingredients: a vehicle, fixative and odour producing substance. 

 

(a) Vehicle or solvent: The role of the solvent is to keep the odour producing substances in solution. Ethanol and water mixture is the most common vehicle used in perfumery. 

 

(b) Fixative: The function of the fixative is to equalize the rate of evapouration of various odouriferous components of the perfume by suitably adjusting their volatility. Sandal wood oil finds use as fixative. Other substances used as fixative are benzoin, glyceryl diacetate and esters of cinnamyl alcohol. 

 

Odoriferous substance 

 

Both natural and synethetic substances are used to impart odour to a perfume. For example: terpenoids like linalool which occur in essential oils are natural odour producing compounds while anisaldelhyde (p – methoxy benzal dehyde) is a synthetic odour producing compound. 

 

3. Talcum powder 

 

Talcum powder is used to reduce irritation of the skin. Talcum powder like face powders contain talk (Mg3(OH)2Si4O10). Chalk, zinc oxide, zinc sterate and suitable perfume act as the other main constituents of talcum powder. Often specific ingredients like antiseptic and cooling agents are added. The role of the talk is to act as a powder base and to make skin smooth. Chalk absorbs secretion (perspiration) without showing any evidence of such absorption. Zinc oxide masks enlarged pores and mirror blemishes, whereas zinc makes powder adhere to skin. Baby talcum powder contain considerable amounts of zinc sterate for adhesiveness and boric acid, for antiseptic purposes. Talcum powders need to be dusted with care to prevent inhalation of the fine particles which irritate the lungs. 

4. Deodorants 

 

As the name suggests, deodorants are applied primary to mask the body odour. The body odour results from the bacterial action following perspiration. A deodorant must therefore, possess antibacterial properties. Aluminium salts have been found to possess excellent antibacterial properties. In addition to aluminium salts, ZnO and (C17H35COO)2Zn also find use in deodorants preparation because they are astrinagents as well as antiseptics. 

NEW HIGH PERFORMANCE MATERIALS 

 

Carbon fibres 

 

Carbon fibres are a new breed of high performance materials. Which have attracted world wide attention and hold great promise for the future? This is because of the fact that these fibres are stronger than steel, stiffer than titanium and lighter than aluminium. These qualities have placed carbon fibres on top of the list of many moved materials available today. Carbon fibres are produced in number of ways and form a variety of starting materials or precurors such as viscose rayon, polyacrylonitrile, pitch, resins, gases such as (methane, and benzene). Their characteristics are strongly influenced by the manufacturing techniques employed. 

 

Carbon fibres reinforced in a right weight matrix, generally on expoxy resin, polyester resin or polyamide are called carbon fibre reinforced plastics (CFRP). When the carbon fibre are reinforced in a carbon matrix, they are known as carbon fibre reinforced carbon (CFRC), commonly known as carbon – carbon composites. 

 

On the basis of their reinforced of carbon fibres carbon fibre reinforced plastics (CFRP) and carbon fibre reinforced carbons (CFRC). Their applications can be broadly classified in to three categories: 

 

1. High technology sector including aerospace, military and nuclear fields. 

 

2. General engineering sector including sports transportation and chemical fields. 

 

3. Biomedical sector: In the aerospace sector, the composites are used for air craft using, tail parts, helicopter rolor blades and using spoilers. The floor decking of air ships is also made from carbon fibre-reinforced composites. Interest in applications involving helicopters continues and it is believed that the first all composite aircraft to fly will be helicopter. Helicopter rolor blades made form CFRP not only give better performance but are less expensive than the metal blades. 

Carbon fibre in the form of carbon fibre reinforced carbon commonly known as carbon composites brakes perform three to five times better than their steel counter parts. 

 

The high thermal conductivity of carbon fibres enhances the heat dissipation in components such as well materials of nuclear fission reactor, gears brakes pads, bearing, fan blades, automobile parts and other friction related products. Further the low coefficient of thermal expansion makes it possible to design structures with zero or very low planar thermal expansion. 

 

Carbon fibres in the form of CFRP find mainly used in the area of sports goods. Very superior specific strength and stiffness, coupled with good fatigue, resistance, make them versatile materials for fishing rods, sky poles, tennis and badminton rockets, racing cycle frames and racing car bodies. 

In the biomedical field, carbon fibres have exciting applications, such as components of bone plates hip joint prostheses, ligaments and hydraulic motors for artificial heart implants. Activated carbon fibres are finding increasing applications in appliances for water treatment, gas masks, air filters, catalyst carriers for platinum and so on. Activated carbon fibres in textile form are used in extremely hostile environments. The main advantages of using carbon fibres are that they can be woven in any form and a surface area of as high as 3000m2/g can be obtainssed. 

Carbon fibres in India are mainly used in defence sector as nose tips and head shields of missiles (like ‘agni’) by DRDO, Hyderabad, and in the aerospace sector by ISRO and other aerospace organization for producing components parts, nozzles of rocket/missiles.

 

CERAMICS 

Ceramics are inorganic non-metallic, covalent network solids that can be made into a paste and shaped at normal temperature which when fired at high temperature gain strength e.g. clays, aluminum oxide, silicon nitride, silicon carbide and crystalline and amorphous silicon dioxide. Ceramics are lighter, stiffer and much more resistant to corrosion, most ceramics are electrical insulators. Ceramics tend to have thermal expansion but low thermal conductivity as a result sudden local temperature charge causes cracking. Sialon, a ceramic alloy is almost as hand as diamond, as strong as steels and as light as aluminum such alloys can be used at temperature of up to 1300oC and require no lubrication 

 

CHEMICALS IN FOOD 

 

Artificial sweeteners 

 

The artificial sweeteners are another type of food additives. The first popular artificial sweetener was saccharin. It was marketed as its water soluble sodium or calcium salt. Saccharin is approximately 300 times sweeter than cane sugar. It has proved to be a lifesaver for countless diabetics and is so great value to people who need to control intake of calories. 

 

Besides saccharin, the other commonly marketed artificial sweeteners are described here. 

 

Aspartame is unstable at cooking temperatures, limiting its use as sugar substitute to cold foods and soft drinks. Alitame is more stable than aspartame during cooking. Sucralose is predicted to become a great commercial successes. 

 

Preservatives 

 

Platability and wholesomeness of many foods reach a peak at harvest time. Often food is most appetizing when it comes form the production lime in the food processin plant. However, during storage and distribution 

 

Undesirable changes occur in flavour, colour, texture and appetite appeal. The food producers use various preservative to delay these changes. The preservative prevent spoilage of food due to microbial growth. The most common preservative used is sodium benzoate, C6H5COONa. It is metabolized by conversion to hippuric acid, C6H5CONHCH2COOH which ultimately is excreted in the urine. Salt of propionic acid and sorbic acid are also used as preservatives. Potassium metal bisulphite is used for this preservation of colourless food material such as fruit juice, squashes etc. 

Edible colours 

 

Edible colours used for good food are essentially dyes. The use of dyes is extremely wide spread. They are used to colour every thing from meat to fruit. For example dyes are used to dye orange peels so that oranges retain their colours. Colours is one of the ingredients in fruits juices. Tetrazine a very widely used dye. Natural dyes like carotene are safe food edible colours. 

 

Antioxidants are added to the food to retard the action of oxygen on the food. e.g. butylated hydroxy toluene (BHT). 

Butylated hydroxyanisole (BHA) is a widely used antioxidants used to preserve oil, fats, butter etc. Vitamin E is a natural antioxidant. 

Antioxidants are added to the food to retard the action of oxygen on the food. In order to prevent rancidity antioxidants are added to oils and fats.

Butyrate hydroxyanisole (BHA) is a widely used antioxidants used to preserve edible oils, fats, better etc. Vitamin E is a natural antioxidants another antioxidants which is commonly used is butylated hydroxytotunce (BHI)

Potassium metals sulphite or sodium metasisulphite is used for the preservation of colourless food materials such as fruits juices, so washes, apples, lichies.

 

DETERGENTS 

Detergents are substances which remove dirt and have cleansing action in water

These are two types of detergents

1. Soapy detergents or soaps
2. Non-soapy detergents or soapless soaps
3. Soap

A soap is a sodium or potassium salt of some long chain carboxylic acids (fatty acids). Sodium salts of fatty acids are known as hard soaps and potassium salts of fatty acids are known as soft soaps. Hard soaps are used for washing purpose and soft soaps are used as toilet soaps, shaving creams and shampoos. Some examples of soap are sodium stearate, , sodium palmitate, and sodium oleate. .

Soap is prepared by heating oil or fat of vegetable or animal origin with concentrated sodium hydroxide solution.

 

2. Non-soapy detergent or synthetic detergents

This is the sodium salt of a long chair benzene sulphuric acid or the sodium salt of a long chain alkyl hydrogen sulphate, synthetic detergents are prepared by reacting hydrocarbons from petroleum with concentration. Sulphuric acid and converting the product into its sodium salts. e.g

 

Anionic detergents

 

Cationic detergents

 

Non – ionic detergent (CH3(CH2)16COO(CH2CH2O)n.CH2CH2OH

 

Advantages of synthetic detergents over soaps

 

(a) Synthetic detergents can be used even in hard water whereas some of the soap gets wasted if water is hard.

 

(b) Synthetic detergents have a strong cleansing action than soaps

 

ROCKET PROPELLANTS

 

The fuels used for launching rockets are called rocket propellants. In general, a rocket propellant consists of a fuel and an oxidiser. Depending upon the physical state of the propellant, these are classified into the following categories: 

1. Solid propellants 

 

Solid propellants use a solid fuel and a solid oxidiser. These are further divided into the following two classes. 

 

(i) Composite propellants 

 

These propellants use polymeric binder such as polyurethane or piolybutadiene as a fuel and ammonium perchlorate as the oxidiser. Some additives such as finely divided magnesium or aluminium metal along with the fuel. 

 

(ii) Double base propellants 

 

These propellants use nitroglycerine (liquid) and nitro cellulose (solid) constituting a gel.  

 

2. Liquid propellants 

 

Liquid propellants are usually classified as either storable or cryogenic. The cryogenic systems generally show high performance. 

However, on the basis of number of liquid used in the fuel. The liquid propellants are usually classified into the following two types 

 

(i) Monopropellants 

 

Liquid propellants in which a single chemical substance acts both as a fuel as well as an oxidizer are called monopropellant. These propellants on ignition or decomposition produce a very large volume of gases. Some examples of monopropellants are: 

 

Methyl nitrate (CH3ONH2), nitromethane (CH3NO2) and hydrogen peroxide (H2O2). 

 

(ii) Biliquid propellants 

 

These consist of two liquids one of which acts as a fuel while the other acts as the oxidiser. Most commonly used liquid fuels are kerosene, alcohol, hydrazine, monomethyl hydrazine (MMH), unsymmetrical dimethyl hydrazine (UDMH) or liquid hydrogen while the most commonly used oxidizers are liquid  oxygen, liquid nitrogen tetraoxide (N2O4) or nitric acid. 

 

3. Hybrid propellants

 

Hybrid propellants consist of a solid fuel and a liquid oxidizer e.g. a mixture of acrylic rubber and liquid dinitrogen tetraoxide.

Advantages 

 

Bi-liquid propellants have two advantages over the solid propellants. They are: 

(i) Bi-liquid propellants give higher thrust than solid propellants. 

(ii) Their thrust can be controlled by regulating the flow of propellants. 

(iii) Hybrid propellants: It consist of a solid fuel and a liquid oxidizer e.g. a mixture of acrylic rubber and liquid dinitrogen tetraoxide. 

 

INSECT SEX ATTRACTANTS (PHEROMONES)

Pheromones are compounds produced by organism for the propose of communicating with the other members of the same species.

To attract members of the opposite sex

To spread an alarm 

To marks the trail to food

To send the message to congregate

e.g. (i) the pheromones muscular in the sex pheromones of common housefly  

(i)

(ii) Bomloykol is the sex hormone of natural silk worm

 

(iii) Heptan-2-one is a component of alane pheromones of bees.

 

(iv) Cockroach undercave as an aggregation pheromones

Many sex attractants have been synthesized and are used to attract the insects into traps. As a means of insect control.

 

Insect repellants

 

Dimethylphthalate is a good mosquito repellant, N, N-diethyl-meta-toluamide (dect) is active against flies, mosquitoes and many other insects, N,N-diethylbenzamide in the active component of many mosquito repellants creams.

SOLVED PROBLEMS

 

Subjective:

 

Prob 1. What are chromophore & chromogen? What is necessary for column chromophores or column bearing substance? 

 

Sol. The presence of chromophore is not sufficient for colour. To make a substance coloured, the chromophore has to be conjugated with an extensive system of alternate single and double bonds as exists in aromatic compounds. A coloured compound having a chromphrore is known as chromogen. 

 

Prob 2. What are auxochromes? 

 

Sol. Certain groups, while not producing colour themselves, when present alongwith a chromophore in an organic substance intensify the colour. Such colour assisting groups are called auxochromes. The auxochromes are acidic or basic functional groups. Example 

Acidic → ⎯OH (Hydroxy), ⎯SO3H (Sulphonic), ⎯COOH (Carboxylic) 

Basic → ⎯NH2 (Amino), ⎯NHR (alkyl acid), ⎯NR2 (dialkyl amine)

 

Prob 3. Which groups are responsible for colour? 

 

Sol. The colour of the organic compound is due to the presence of certain multiple bonded groups called chromophores. 

 

Prob 4. What are hard soaps and soft soaps? Give examples of soaps

 

Sol. Sodium salts of long chain fatty acids are known as hard soaps. They are prepared form cheep oils and fats and sodium hydroxide. They contain free alkali and are used for washing purpose. Potassium salts of long chain fatty acids are known soft soaps. Soft soaps are prepared from good oils and potassium hydroxide. They do not contain free alkali, produce more lather and are used as toilet soaps, shaving creams and shampoos.

Example

       

 

Prob 5. What are the advantages of liquid propellants over solid propellants?

 

Sol. The main advantage of liquid propellants are

(a) They give a better thrust than solid propellants

(b) Their thrust can be controlled by regulating the flow of propellants.

Prob 6. Describe broad spectrum antibiotics.

Sol. Antibiotics which are affective against several different types of harmful micro-organism and thus, capable of curing several infections are called broad spectrum antibiotics.

Example Tetracyclines, chloromycetine

 

Prob 7. Describe the distinguishing features of acid and basic dyes. 

 

Sol.

Acid dye	Basic dye
1. They contain sodium salt of organic acid, such as sulphonic acid, carboxylic acid and phenols	1. They contain the salts of organic basis i.e. ⎯NH2 group, ⎯NR2 group.
2. They are used for dying natural silk, wool and nylon but can not dye cotton.	2. They are used to dye nylon wool, leather, paper, polyester as well as cotton.
3. The acidic groups serve as reactive points for fixing the dye to the fibre.	3. In acidic solution the cations of ⎯NH2 or ⎯NR2 groups are the reactive site and are used to attach to the fabric.

 

Prob 8. Give one important use of each of the following 

(i) Bithional 

(ii) Chloroamphenicol 

(iii) Streptomycin 

(iv) Paracetamol 

 

Sol. (i) Biothional (antiseptic) is used in the soap to reduce the odours produced by the bacterial decomposition of organic matter on skin. 

(ii) Chloroamphenicol (antiseptic) is used to cure typhoid, dysentry and urinary infections. 

(iii) Streptomycin (antiseptic) is used for curing tuberculosis. 

(iv) Paracetamol (antipyretic) is used to bring down the body temperature. 

 

Prob 9. What is AZT? 

 

Sol. AZT ⎯→ (3’ – azido – 3’ deoxythymidine) 

It is used as antiviral agent agains HIV – I infection i.e. AIDS. 

AZT does not kill AIDS virus but rather interacts with its ability to reproduce. Thus AZT bites an AIDS infection but does not kill it. 

 

Prob 10. How the energy of a propellants is measured? 

 

Sol. Specific impulse (Is) is the measure of the energy of the propellant which is related to the flame temperature (Tp) of propellant and the average molecular mass (Ma) of the product gases, by the following relation. 

Hence, higher value of Tp  and lower value of Ma makes the propellant better. 

 

Objective:

 

Prob 1. LSD (Lysergic acid diethylamide) is 

(A) sweetening agent (B) synthetic fibre 

(C) psychedelic drug (D) antibiotic 

 

Sol. (A)

 

Prob 2. Which one of the following is a chromophoric group? 

(A) ⎯N = N ⎯ (B) ⎯OH 

(C) ⎯SO3H (D) ⎯NH2 

 

Sol. (A)

 

Prob 3. With which of the following cations, alizarin will impart a rose red colour on the fibric 

(A) Fe3+ (B) Cr3+ 

(C) Ba+2 (D) Al+3 

 

Sol. (D)

 

Prob 4. 2-acetoxy benzoic acid is called 

(A) antiseptic (B) aspirin 

(C) antibiotic  (D) mordant dye 

Sol. (B)

 

Prob 5. Dettol consist of 

(A) cresol + ethanol (B) xylenol + terpinol 

(C) chloroxylenol + terpeneol (D) none of these 

 

Sol. (C)

Prob 6. Which of the following is used in anesthesia? 

(A) N2 (B) N2O 

(C) CH4 (D) CO2 

Sol. (B)

 

Prob 7. Phenol is used as 

(A) an antiseptic (B) an insecticide 

(C) a disinfectant (D) styptic 

 

Sol. (A) & (C)

 

Prob 8. Diazo coupling is useful to prepare some 

(A) vitamin (B) proteins 

(C) dyes (D) pesticides 

 

Sol. (C)

 

Prob 9. The number of chromophores in picric acid is 

(A) 1 (B) 2 

(C) 3 (D) 4 

 

Sol. (C)

 

Prob 10. Which one is a broad spectrum antibiotic? 

(A) procaine (B) plasmoquin 

(C) aspirin (D) chloramphenicol 

 

Sol. (D)

ASSIGNMENT PROBLEMS

 

Subjective:

 

Level – O

 

1. What are the common ingredients of a perfume? 

 

2. Why is colour imparted by azo dyes to fabrics not fast? 

 

3. What is the role of bithional in toilet soaps? 

 

4. Why does 70% sugar syrup act as preservative? 

 

5. What is the function of pH adjusters in cosmetics? 

 

6. Give two example of each: 

(i) Broad spectrum antibiotic 

(ii)  Narrow spectrum antibiotic

(iii) Transquillizer 

(iv) Antipyretic 

(v) Antiseptic 

(vi) Disinfectant 

(vii) Analgesics 

(viii) Sulpha drugs 

 

7. Why is borax added to cold creams? 

 

8. What are active ingredients of a deodrant? 

 

9. What is the difference between a preservative and an antioxidant? 

 

10. Name a substance which can be used both as an antiseptic as well as a disinfectant. 

 

Level – I 

 

1. How are antiseptics distinguished from disinfectants? Give two examples of each of the substances. 

 

2. What are antacids? List some of the compounds, which are used as antacids? 

 

3. Describe the following with suitable examples: 

(i) tranquilizers (ii) antifertility (iii) antihistanmines 

 

4. Given an examples of 

(i) tripnenyl methane dye (ii) azo dye (iii) anthraquinone dye 

 

5. What do you mean by mordant dye? Write the name of two substances which are used as mordant with mordant dye. 

 

6. Give one example each of an azo dye which can be used as an acidic, basic, direct and ingrain dye. 

 

7. Describe the following with one example in each case. 

(i) Preservatives 

(ii) Artificial sweeteners 

(iii) Antioxidants 

(iv) Edible colours 

 

8. Describe the following with one example in each case. 

(i) Double base propellant 

(ii) Biliquid propellant 

(iii) Monoliquid propelltant 

(iv) Hybrid propellant 

 

9. What is the role of an antihistamine? 

 

10. How aniline yellow and methyl orange are prepared. 

 

Level – II 

 

1. Bring out the essential point of difference between acidic dyes and basic dyes. 

 

2. What are the essential components of a talcum powder? What is the role of boric acid in talcum powder? 

 

3. What are deodrants and what is their specific role in cosmetics? 

 

4. What are carbon fibres? How are they designed? Write two important uses of carbon fibres.

 

5. What are super conducting ceramics? Write some uses of superconductor ceramics. 

 

6. Write a brief note on micro alloys. 

 

7. What are biodegradable and nonbiodegradable detergents? What are the consequences of using latter class of detergents? 

 

8. What is propellant? How are various rocket propellants classified? 

 

9. What propellants have been used PSLV-C4 rocket? 

 

10. Describe the following with examples. 

(i) double base propellant 

(ii) biliquid propellant 

(iii) monliquid propellant 

(iv) hybrid propellant 

 

 

 

 

 

Objective:

 

Level – I

 

1. Streptomycin is specific against

(A) Typhoid (B) Tuberculosis

(C) Malaria (D) Whooping cough

 

2. Which of the following is insecticide?

(A) DDT (B) TNT

(C) TNB (D) Aspirin

 

3. The correct structure of drug paracetamol is

(A)		(B)
(C)		(D)

 

4. The compound

is used as

(A) Antiseptic (B) Antibiotic

(C) Analgesic (D) Pesticide

 

5. Which of the following represents a biliquid propellant?

(A) Nitroglycerious + Nitrocellulose

(B) N2O4 + acrylic rubber

(C) N2O4 + unsymmetrical dimethylhydrazine

(D) Poly butadiene + ammonium perchlorate

 

6. Which of the following is an example of basic dye?

(A) Alizarin (B) Malachite

(C) Indigo (D) Orange-1

 

7. Which of the following groups would you introduce into a dye to make it water soluble?

(A) (B)

(C) (D)

 

8. A substance which can act both as an antiseptic and disinfectant is 

(A) Aspirin (B) Phenol

(C) Analgin (D) Sodium pentothal

 

9. Which one of the following is a mordant?

(A) Tannic acid (B) Metallic hydroxide

(C) Salts of Al, Cr, Fe, Sn (D) All of these

 

10. Heroin is derivative of 

(A) Morphine (B) Nicotine

(C) Cocaine (D) Caffeine

 

11. Proserpine is 

(A) Tranquillizer (B) Antibiotic

(C) Vitamin (D) Hormone  

 

12. Ampicillin is 

(A) An analgesic (B) An antibiotic

(C) An antimalarial (D) An antipyretic

 

13. A large number of antibiotics have been isolated from

(A) Bacteria actiuromycetes (B) Bacteria staphylococcus

(C) Bacteria rhizobium (D) Acids

 

14. Gammexane is

(A) Chlorobenzene (B) DDT

(C) Benzene hexo chloride (D) None of these

 

15. Which of the following is used as insect repellants?

(A) Bomloykol (B) Undecane

(C) Both (A) and (C) (D) Dimethylphthalate

16. Sialon, a ceramic alloy, has one of the following properties

(A) It is almost as soft as graphite (B) It is as light as hydrogen

(C) It can be used at temperature of 1300oC (D) None of the above

 

17. In talcum powder, magnesium carbonate is used for

(A) Slipping (B) Opacity 

(C) Absorbency (D) None

 

18. Which of the following statement is correct for a good varnishing cream?

(A) It should be stable under varying climate condition 

(B) It should not have any adverse effect on the stein of the user 

(C) Both (A) and (B)

(D) None

 

19. Which of the following is used for the preservation of colourless food materials such as fruit juices, squashes?

(A) Potassium metalbisulphite (B) Sodium sulphate

(C) Sodium benzoate (D) all of the above

 

20. Bebtylated hydroxyanisole (BHA) is widely used as 

(A) Artificial sweetener (B) Antioxidants

(C) Edible colours (D) Preservatives

 

Level-II

 

1. Which of the following is correct statement for a substance to act as dye?

(A) Presence of chromophore is necessary

(B) Presence of auxochrome group as well as chromophore is necessary

(C) Every coloured substance

(D) All the above

 

2. Which of these is a hypotonic?

(A) Metaldehyde (B) Acetaldehyde

(C) Paraldehyde (D) None of these

 

3. Tranquilizes are the substances used for the treatment of 

(A) Cancer (B) Aids

(C) Mental diseases (D) Blood infection  

 

4. Morphine is

(A) Antiseptic (B) Analgesic

(C) Antibiotic (D) Anesthetic

 

5. Sulpha drugs are use for

(A) Removing bacteria (B) Precipitating bacteria

(C) Stopping the growth of bacteria (D) Decreasing the size of bacteria

 

6. To which class of dyes does phenolphthalein belong?

(A) Azo dyes (B) Nitro dyes

(C) Triphenylmethane dyes (D) Phthalein dyes 

 

7. Which one is an example of vat dye?

(A) Congo red (B) alizarin

(C) Malachite (D) Indigo

 

8. Which of the following is used as monopropellant?

(A)		(B)
(C)	Kerosene	(D)	Alcohol

 

9. Sulpha drugs are derivative of 

(A) Para-aminobenzoic aicd

(B) Para-aminobenzene sulphuric acid

(C) Para- aminobenzene sulphonamide

(D) Para-aminobenzene slphonyl chloride

 

10. Which of the following statement is not true?

(A) Some disinfectants can be used as antiseptics at low concentration 

(B) Sulphadiazine is a synthetic antibacterial 

(C) Ampicillin is natural antibiotic 

(D) Aspirin is both analgesic and antipyretic

 

11. Which one of the following can work as mordant?

(A) NaCl (B) K2SO4

(C) Alum (D) Plaster of pairs

 

12. Dyes can bind to fibers by

(A) Ionic bond

(B) Covalent bond and co-ordinate bond

(C) Hydrogen bond

(D) All of these

13. Which one of the following pairs are correctly matched?

(A) Dettol, chloroxylenol (B) Tranquilizer, aspirin

(C) Antibiotic, brufen (D) Anesthetic, penicillin 

 

14. Which of the following is the sex hormone of natural silk worm?

(A) Muscular (B) Undecame

(C) Bomolykol (D)_Hepta-2-one

15. Which of the following statements is correct for pheromones?

(A) They are to mark the trail to fund (B) To spread an alone

(B) To attract members of the opposite sex (D) All of the above

 

16. The following compounds is

(A) Anionic detergent (B) Cationic detergent

(C) Non-ionic detergent (D) None

 

17. Which of the following statements is correct?

(A) Synthetic detergents are prepared from the hydrocarbons obtained from petroleum

(B) Synthetic detergents are less soluble in water than soaps.

(C) Synthetic detergents have a weaker cleansing action than soaps

(D) All of the above are correct

 

18. Which of the following statements is correct?

(A) Soaps are sodium salts of lower fatty acid

(B) Soaps are prepared form natural oils and fats

(C) Soaps are non-biodegradable 

(D) Both (B) and (C)

 

19. The above reaction is

(A) Polymerization (B) Condensation 

(C) Saponifacation (D) None

 

20. Which one of the following is an example of composite rocket propellant?

(A) Polyurethane, ammonium perchlorate and Al

(B) Polyurethane, ammonium chloride and Mg

(C) Polyurethane, ammonium hydroxide and Al

(D) All of these

 

ANSWERS TO ASSIGNMENT PROBLEM

 

Subjective:

 

Level – O

 

1. These are vehicle, fixative and odour producing substance. 

 

2. In azo compounds photochemical reactions are possible hence the colour of the dye fades when it is exposed to sunlight due to photochemical decomposition. 

 

3. Bithional is used as an antiseptic. It reduces the odour produced by bacterial decomposition of organic matter on skin. 

 

4. Because of having very little free water, 70% sugar syrup inhibit bacterial growth, thus act as preservative. 

 

5. pH adjusters adjust or stabilize the acidity or basicity of cosmetics. Examples: citric acid, ammonium hydroxide. 

 

6. (i) Chloramphenicol, tetracycline 

(ii) Penicillin, streptomycin 

(iii) Luminal, reserpine

(iv) Novalgin, phenacetin 

(v) Chloroxylinol, bithional 

(vi) 1% phenol 

(vii) Aspirin, morphine 

(viii) Sulphadiazine, sulphaguanidine 

 

7. To increases the stability of emulsions present in cold creams. 

 

8. Aluminium salts of strong acids, such as AlCl3, Al2(SO4)3 etc along with zirconium salts such as sodium zirconium lactate. 

 

9. Preservatives protect the food against bacteria, yeasts and moulds but anti oxidants prevent oxidation of fats in processed foods. 

 

10. Phenol 

0.2 % as antiseptic 

1% as disinfectant 

Level – I

 

5. The dye which can not dye the fibre directly but required an additional substance called mordant to bind the dye and fabric is called mordant dye. 

For acid mordant dyes, metal hydroxide (Fe(OH)3 or Cr(OH)3 etc] is used as mordant and with basic mordant dye tannic acid is used as mordant. 

 

6. Acid dyes ⎯→ Orange – I or II 

Basic dyes ⎯→ aniline yellow or butter yellow 

Direct dyes ⎯→ Congo red 

Ingrain dye ⎯→ para red 

 

9. The role of antihistamine is to check the production of histamine and combat the effect of allergy. Example benadryl and trimeton. 

10.	(i)
	(ii)

 

 

 

Objective:

Level – I

1. B 2. A 3. B
2. C 5. C 6. C
3. C 8. B 9. D
4. A 11. A 12. B
5. A 14. C 15. D
6. C 17. C 18. C
7. A 20. B

 

Level – II

 

1. B 2. C 3. C
2. B 5. C 6. D
3. D 8. A 9. C
4. C 11. C 12. D
5. A 14. C 15. D
6. A 17. A 18. B
7. A 20. A