Chemistry in everyday life
Chemistry plays a significant role in our everyday life, from the food we eat and the medicines we use to the materials and products that surround us. Many concepts in chemistry, especially in topics like polymers, drugs, soaps, detergents, and food preservatives, are not only important for different kind of examinations but also help us understand how science improves human life. Students often find these topics easy to understand but difficult to remember during exams due to confusing definitions and lack of clarity. To help students overcome this problem, this article presents clear, precise, and exam-oriented questions and answers written in a simple and student-friendly manner. Each answer is structured to match the style expected in board exams, competitive exams, and viva-voce in practical examinations.
Q1. What are antacids? Give example
A) Antacids are chemical compounds that neutralise the excess acid in stomach and maintain pH at normal level.
Ex: aluminium hydroxide, magnesium hydroxide,aluminium phosphate.
Q2. What are artificial sweetening agents? Give examples The chemical substances which possess sweetness like natural sweeteners are known as artificial sweetening agents.
ex: Alitame, Saccharine,Sucralose,aspartame. Glucose and Fructose are natural sweeteners.
Q3. What are disinfectants? Give examples
The substances which are capable of destroying the microorganisms and are harmful to the living tissues.
Ex: 1% phenol, aq. solution of chlorine.
Q4. What are analgesics? Give examples
Analgesics are the compounds which relieve all sorts of pain without loss of consciousness. There are two types of analgesics.
a) narcotic analgesics : ex: Morphine, heroin.
b) non-narcotic analgesics: ex: Aspirin,paracetamol, Ibuprofen
Q5. What are non-narcotic analgesics? Give examples
A) Non-narcotic analgesics have no addictive properties. They are used to relieve mild aches like headache and toothache. They are non addictive and do not produce toxic effects.
Ex: Aspirin, Ibuprofen, paracetamol
Q6.What are narcotic analgesics? Give examples
A) Narcotic analgesics are addictive drugs. They are used for the relief of severe pains such as post operative pain, cold pain, cancer pain, morphine. High doses cause coma, convulsions and stupor
ex: Morphine, codeine.
Q7. What are tranquilizers? Give example
A) Drugs used in the management and treatment of stress and mental diseases are called tranquilizers. These are neurologically active drugs. They involve in message transfer mechanism from nerve to receptor.
Eg: barbituric acid, Luminal, Amytal.
Q8. What are antibiotics? Drugs used to cure diseases caused by microorganisms or microbes, such as bacteria, viruses, fungi etc are called antibiotics.
ex: penicilline(wonder drug), sulphanilamide
Q9) What are food preservatives? Give example
Chemical substance which prevents the spoilage of food materials by destroying the food spoiling microorganisms is called a food preservatives.
Ex: Sodium benzoate, Salt
Q10) What is the difference between a soap and a synthetic detergent?
Soap is sodium or potassium salt of higher fatty acids, whereas synthetic detergents are sodium salts of sulphonated long chain alcohols or may be quaternary ammonium salts or amine soaps. Soaps cannot give foam with hard water whereas synthetic detergents give foam with hard water.
Q11) What is polymerization? Give examples
The process in which monomers linked together by covalent bonds to give polymer is known as polymerization.
Ex: n(CH₂=CH₂) → (–CH₂–CH₂–)ₙ
(ethylene) polyethylene
Q12) What is addition polymers? Give example
Polymers formed due to addition of molecules of same (or) different monomers without elimination of any atom (or) group are known as addition polymers.
Ex: polythene, Buna-N, Buna-S
Q13) What are co-polymers? Give example
Polymers formed by two (or) more types of monomeric units are called co-polymers.
Ex: Nylon-66, Buna-N, Buna-S etc.
Q14) What are elastomers? Give example
Polymers in which the intermolecular forces are strong due to H-bonding (or) dipole-dipole interactions and forces of attraction between the polymer chains are weak are known as elastomers. These are stretched polymers.
Ex: Natural rubber, Buna-N, Buna-S
Q 15) What are thermoplastic polymers? Give example
The linear (or) slightly branched polymers, which becomes soft on heating and hard on cooling are called thermoplastic polymers.
Ex: polythene, PVC, Teflon
Q16) What are fibres? Give example
Polymers in which the intermolecular force of attraction between the polymer chains due to H-bonding (or) dipole-dipole interactions are called fibres.
ex: polyamides, polyesters etc.
Q 17) What is Ziegler -Natta catalyst?
The mixture of triethyl aluminium and titanium tetrachloride is known as Ziegler-Natta catalyst (Ti Cl₄ + Al(C₂H₅)₃). It is used in the polymerisation of ethene (or) ethylene.
Q 18) What is the difference between Buna-N and Buna-S?
i) Buna-N and Buna-S differs in their monomers.
ii) The monomers of Buna-N are 1,3-butadiene and acrylonitrile.
iii) The monomers of Buna-S are 1,3-butadiene and styrene.
Q 19) What is PDI (Polydispersity Index)?
The ratio between weight average molecular mass and number average molecular mass of the polymer is known as polydispersity index.
PDI = M w / Mn