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GS Paper IUPSC Prelims 2002
Health & Medicine
Question No. 327Interactive Test Mode
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Q327. Assertion(A): Synthetic detergents can lather well in hard water. Reason (R): Synthetic detergents form soluble calcium and magnesium salts with hard water.

Assertion(A): Synthetic detergents can lather well in hard water. Reason (R): Synthetic detergents form soluble calcium and magnesium salts with hard water.

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Official Answer Key & Detailed Solution

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Official UPSC Answer KeyUPSC Prelims 2002 • Science and Technology

Correct Answer: Option (A) — Both A and R are individually true and R is the correct explanation of A

Concept & Option Breakdown

Standard Reference Verified

Assertion (A) is true: Synthetic detergents work effectively and lather well even in hard water. Reason (R) is true: Unlike soaps (which form insoluble calcium/magnesium precipitates known as scum), synthetic detergents (sulfonates/sulfates) form soluble calcium and magnesium complexes/salts, allowing them to retain their cleansing and foaming properties. Therefore, Reason (R) is the correct explanation of Assertion (A).

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Question Specifications & Syllabus Mapping

Examination & YearUPSC Civil Services Preliminary Examination 2002 (Q327)
Paper & Marking SchemeGS Paper I • 2 Marks (-0.66 Negative for incorrect response)
Syllabus Subject & TopicScience and Technology → Health & Medicine
Official Answer KeyOption (A) — Both A and R are individually true and R is the correct explanation of A

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Frequently Asked Questions — UPSC Prelims 2002 Q327

What is the official answer for UPSC Prelims 2002 GS Paper I Question 327 (Science and Technology)?

The official UPSC answer key for this 2002 Science and Technology (Health & Medicine) question is Option (A): "Both A and R are individually true and R is the correct explanation of A". Correct attempts carry 2 Marks with -0.66 Negative penalty for wrong answers.

Which UPSC Prelims syllabus topic does this 2002 question belong to?

This question belongs to GS Paper I under the subject "Science and Technology" and micro-topic "Health & Medicine". You can explore all repeated questions from Health & Medicine in Acme AI's 3D Prelims PYQ Realm or practice 50 full-length and sectional tests in the APT Prelims Test Series.

How can I solve this Health & Medicine UPSC Prelims question using option elimination?

To solve Health & Medicine questions in UPSC Prelims, identify extreme modifiers, verify core NCERT conceptual definitions, and eliminate mutually contradictory statement pairs before locking your final option.

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