Match List - I with List - II and select the correct answer from the codes given below the lists :
List - I
A. Kevlar
B. Taxol
C. Zinc Phosphide
D. Nitrocellulose
List - II
1. Explosive
2. Synthetic f

Question

Match List - I with List - II and select the correct answer from the codes given below the lists :
List - I
A. Kevlar
B. Taxol
C. Zinc Phosphide
D. Nitrocellulose
List - II
1. Explosive
2. Synthetic fibre
3. Anticancer drug
4. Rodenticide
Codes :

UnlockIAS · Accepted Answer

Correct — B, A-2, B-3, C-4, D-1. Kevlar is a synthetic fibre: an aramid (aromatic polyamide) developed by Stephanie Kwolek at DuPont in 1965, whose stiff, closely packed polymer chains make it, weight for weight, stronger than steel — hence its use in bullet-resistant vests, helmets, ropes and tyre reinforcement. Taxol (paclitaxel) is an anticancer drug, originally isolated from the bark of the Pacific yew and used against ovarian, breast and lung cancers; it works by locking microtubules in place so that a dividing cell cannot pull its chromosomes apart. Zinc phosphide is a rodenticide: eaten in bait, it meets the acid of the rodent's stomach and releases the highly toxic gas phosphine. Nitrocellulose is an explosive — 'guncotton', made by nitrating cotton or wood cellulose with nitric and sulphuric acid, and the basis of smokeless propellant powders. Only option (b) puts all four in their right places.

Why the other options are wrong — (a) This is the near-miss and the intended trap: it gets Kevlar and nitrocellulose right but swaps the middle pair, making Taxol a rodenticide and zinc phosphide an anticancer drug. Taxol is a plant-derived chemotherapy agent; zinc phosphide is a rat poison and has no medical use.  (c) Only Taxol is placed correctly. Kevlar becomes a rodenticide, zinc phosphide an explosive and nitrocellulose a synthetic fibre — all wrong. (Nitrocellulose was in fact used for the very first artificial silk in the 1880s, but in exam terms it is the explosive, and the fibre in this list is Kevlar.)  (d) Every pairing is wrong. It turns Kevlar into a drug, Taxol into an explosive, zinc phosphide into a fibre and nitrocellulose into a rat poison — a shuffled option that can be eliminated the moment you know any one of the four substances.

Concept: This is a 'substance to use' matching question, the commonest chemistry format in state PCS papers. The four items are drawn from four different applied fields — polymer engineering, pharmacology from natural products, pest control and explosives chemistry — so no single subject textbook covers all of them. What makes them memorable is that each name carries its own clue: Kevlar belongs to the aramid family of high-strength fibres; Taxol takes its name from the genus Taxus, the yew; zinc phosphide is a phosphide, and phosphides release phosphine on contact with acid; nitro- prefixes in organic chemistry (nitroglycerine, trinitrotoluene, nitrocellulose) almost always signal an explosive.

State PCS 2019 Q88 — Science & Technology PYQ with Answer

State PCS 2019 Q88 — Science & Technology PYQ with Answer