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प्रश्न
Assertion (A): Melting point and boiling point of ethanol are lower than that of sodium chloride.
Reason (R): The forces of attraction between the molecules of ionic compounds are very strong.
विकल्प
Both Assertion (A) and Reason (R) are true and Reason (R) is the correct explanation of (A).
Both Assertion (A) and Reason (R) are true but Reason (R) is not the correct explanation of (A).
Assertion (A) is true, but Reason (R) is false.
Assertion (A) is false, but Reason (R) is true.
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उत्तर
Both Assertion (A) and Reason (R) are true and Reason (R) is the correct explanation of (A).
Explanation:
- Assertion (A) is true because ethanol (a covalent compound) has much lower melting and boiling points compared to sodium chloride (an ionic compound).
- Reason (R) is also true because ionic compounds like sodium chloride have very strong electrostatic forces of attraction between ions, which require a large amount of energy to break.
- These strong forces are the reason why sodium chloride has high melting and boiling points, correctly explaining the assertion.
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