Every Book Back multiple-choice question from Chemistry in Everyday Life (12th Standard Chemistry, Samacheer Kalvi) — each with the correct option highlighted and a clear, worked explanation. Free to read in English and Tamil.
Q1
Which of the following is an analgesic?
- A. Streptomycin
- B. Chloromycetin
- C. AspirinCorrect
- D. Penicillin
Explanation. Aspirin is an analgesic drug used to relieve pain and reduce inflammation. Streptomycin and penicillin are antibiotics, whereas chloromycetin is also an antibiotic.
Q2
Antiseptics and disinfectants either kill or prevent the growth of microorganisms. Identify which of the following statements is not true.
- A. Dilute solutions of boric acid and hydrogen peroxide are strong antiseptics.Correct
- B. Disinfectants harm the living tissues.
- C. A 0.2% solution of phenol is an antiseptic while a 1% solution acts as a disinfectant.
- D. Chlorine and iodine are used as strong disinfectants.
Explanation. Dilute boric acid is a very weak antiseptic used specifically as an eye wash, rather than a strong antiseptic. The other statements regarding disinfectants and phenol concentrations are chemically accurate.
Q3
Drugs that bind to the receptor site and inhibit its natural function are called:
- A. AntagonistsCorrect
- B. Agonists
- C. Enzymes
- D. Molecular targets
Explanation. Antagonists are drugs that bind to receptor sites and block or inhibit their natural biological signals. Agonists mimic natural messengers to initiate a biological response.
Q4
Aspirin is chemically known as:
- A. Acetylsalicylic acidCorrect
- B. Benzoyl salicylic acid
- C. Chlorobenzoic acid
- D. Anthranilic acid
Explanation. Aspirin is synthesized by the acetylation of salicylic acid, which chemically yields acetylsalicylic acid.
Q5
Which one of the following structures represents Nylon-6,6 polymer?
- A. (figure A)
- B. (figure B)
- C. (figure C)
- D. (figure D)Correct
Explanation. Nylon-6,6 is identified by matching its structural linkages and polymer repeating units to amide groups formed from hexamethylenediamine and adipic acid.
Q6
Natural rubber has which of the following configurations?
- A. Alternate cis- and trans-configuration
- B. Random cis- and trans-configuration
- C. All cis-configurationCorrect
- D. All trans-configuration
Explanation. Natural rubber is cis-1,4-polyisoprene, which contains only cis-double bonds along the polymer backbone, making it highly elastic.
Q7
Nylon is an example of a:
- A. PolyamideCorrect
- B. Polythene
- C. Polyester
- D. Polysaccharide
Explanation. Nylons are synthetic polymers characterized by repeating amide bonds (-CO-NH-) in their backbone, classifying them as polyamides.
Q8
Terylene is an example of a:
- A. Polyamide
- B. Polythene
- C. PolyesterCorrect
- D. Polysaccharide
Explanation. Terylene, also known as Dacron, is synthesized by condensing ethylene glycol and terephthalic acid, creating ester linkages in the chain.
Q9
Which of the following is the monomer of neoprene?
- A. \(CH_2=C(Cl)-CH=CH_2\)Correct
- B. \(CH_2=C(CH_3)-CH=CH_2\)
- C. \(CH_2=CH-CH=CH_2\)
- D. \(CH_2=C(Cl)-C(Cl)=CH_2\)
Explanation. Neoprene is a synthetic rubber produced by polymerizing 2-chlorobuta-1,3-diene, commonly known as chloroprene.
Q10
Which of the following is a biodegradable polymer?
- A. HDPE
- B. PVC
- C. Nylon 6
- D. PHBVCorrect
Explanation. PHBV is a copolymer of 3-hydroxybutanoic acid and 3-hydroxypentanoic acid, which is readily degraded by microbes in the environment.
Q11
Non-stick cookware generally carries a coating of a polymer whose monomer is:
- A. Ethane
- B. Prop-2-enenitrile
- C. Chloroethene
- D. TetrafluoroetheneCorrect
Explanation. Non-stick pans are coated with Teflon, which is polytetrafluoroethylene (PTFE), synthesized from the monomer tetrafluoroethene.
Q12
Assertion: 2-methyl-1,3-butadiene is the monomer of natural rubber.
Reason: Natural rubber is formed through anionic addition polymerization.
- A. If both assertion and reason are true and the reason is the correct explanation of the assertion.
- B. If both assertion and reason are true but the reason is not the correct explanation of the assertion.
- C. Assertion is true but the reason is false.Correct
- D. Both assertion and reason are false.
Explanation. The monomer of natural rubber is isoprene, which is 2-methyl-1,3-butadiene. However, natural rubber is formed via coordination polymerization rather than anionic addition.
Q13
Which of the following is a copolymer?
- A. Orlon
- B. PVC
- C. Teflon
- D. PHBVCorrect
Explanation. PHBV is synthesized from two different monomer species, whereas Orlon, PVC, and Teflon are homopolymers synthesized from a single monomer type.
Q14
The polymer used in making blankets (artificial wool) is:
- A. Polystyrene
- B. PANCorrect
- C. Polyester
- D. Polythene
Explanation. Polyacrylonitrile (PAN) is used as a synthetic wool substitute under trade names such as Orlon to manufacture sweaters and blankets.
Q15
Regarding cross-linked or network polymers, which of the following statements is incorrect?
- A. Examples are Bakelite and melamine.
- B. They are formed from bi- and tri-functional monomers.
- C. They contain covalent bonds between various linear polymer chains.
- D. They contain weak covalent bonds in their polymer chain.Correct
Explanation. Cross-linked polymers contain strong, stable covalent bonds that link the linear chains together, giving them high structural rigidity.
Frequently asked questions
How many MCQs are there in Chemistry in Everyday Life?
This chapter has 15 book-back multiple-choice questions, each with the correct answer and a step-by-step explanation.
Are these 12th Standard Chemistry MCQs free to practise online?
Yes. Every question, answer and explanation here is free, and you can also take them as a timed practice test.
Where can I find the Chemistry in Everyday Life book-back answers?
The correct option for each question is highlighted on this page with a worked explanation, plus a quick answer-key summary at the top.
