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Science (086) — AI-generated practice question

AI-generated practice question — model-generated for extra practice, not a previous-year CBSE board question.

Q1. [1] straightforward exam-ready
Assertion (A): Ionic compounds generally have high melting and boiling points. Reason (R): A large amount of energy is needed to overcome the strong electrostatic forces of attraction between oppositely charged ions. (A) Both A and R are true, and R is the correct explanation of A. (B) Both A and R are true, but R is NOT the correct explanation of A. (C) A is true but R is false. (D) A is false but R is true.
  1. A Both A and R are true, and R is the correct explanation of A.
  2. B Both A and R are true, but R is NOT the correct explanation of A.
  3. C A is true but R is false.
  4. D A is false but R is true.
Generated by claude-sonnet-4-6 · 2026-06-26 01:05 · grounding rag
Model Answer

(A) Both A and R are true, and R is the correct explanation of A.

Ionic compounds have high melting and boiling points because a considerable amount of energy is required to break the strong electrostatic forces of attraction between oppositely charged ions.

Source: Chapter 3, Section 3.3.1 Properties of Ionic Compounds

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Explanation

The textbook explicitly states: "Ionic compounds have high melting and boiling points. This is because a considerable amount of energy is required to break the strong inter-ionic attraction." Both the assertion and reason are factually correct, and the reason directly and correctly explains the assertion — so option (A) is the answer. Don't confuse this with covalent compounds, which have low melting/boiling points due to weak intermolecular forces.

Previous-year CBSE Grade 10 board exam questions, organised by subject and chapter, each with a model answer — free to read and print.