Match List I with List II and select the correct answer using the codes given below the Lists: List I List II I. German Silver A) Tin II. Solder B) Nickel III. Bleaching Powder C) Sodium IV. Hypo D) Chlorine

Q 9 / 17

UPSC CSE Prelims 2000

Match List I with List II and select the correct answer using the codes given below the Lists:

List I	List II
I. German Silver	A) Tin
II. Solder	B) Nickel
III. Bleaching Powder	C) Sodium
IV. Hypo	D) Chlorine

EXPLANATION

Correct Option : D

The correct matching is as follows:

German Silver is an alloy primarily composed of copper, zinc, and nickel. Therefore, I matches with B (Nickel).
Solder is a fusible metal alloy used to create a permanent bond between metal workpieces. It typically consists of tin and lead. Therefore, II matches with A (Tin).
Bleaching Powder (calcium hypochlorite, Ca(ClO)₂) is produced by the reaction of chlorine gas with calcium hydroxide. Therefore, III matches with D (Chlorine).
Hypo, or sodium thiosulfate (Na₂S₂O₃), is a chemical compound commonly used in photographic processing. Therefore, IV matches with C (Sodium).

Based on these pairings, the correct code is I-B, II-A, III-D, IV-C.

Incorrect Options:

Options A, B, and C present incorrect combinations of the substances in List I with their corresponding components or related elements in List II. For instance, Option A incorrectly associates German Silver with Tin and Solder with Nickel. Option B incorrectly links German Silver with Tin and Bleaching Powder with Sodium. Option C incorrectly pairs German Silver with Tin and Hypo with Chlorine. These discrepancies render them incorrect as per the established chemical compositions and industrial applications of the substances.