Question

Assertion: Specific heat capacity of a substance is a constant quantity.

Reason: It is the amount of heat energy required to raise the temperature of 1 g of a substance by 1 °C. As with the mass, the temperature and the nature of the substance do not change. So, it is a constant quantity.

• A. Both ‘A’ and ‘R’ are correct and ‘R’ is the correct explanation of ‘A’.
• B. Both ‘A’ and ‘R’ are correct, but ‘R’ is not the correct explanation of ‘A’.
• C. ‘A’ is correct, but ‘R’ is incorrect
• D. ‘A’ is incorrect, but ‘R’ is correct

Answer 1

The correct option is A

Both ‘A’ and ‘R’ are correct and ‘R’ is the correct explanation of ‘A’.

The explanation for the assertion:

1. The amount of heat required to raise the temperature of a unit mass of a substance through 1 °C or 1 K is called specific heat capacity (c).
2. In the SI system, the unit of specific heat capacity (c) is J kg^-1 K^-1.
3. It is a constant quantity for a given substance.

The explanation for the reason:

1. The amount of heat required to raise the temperature of a unit mass (or 1 g) of a substance through 1 °C or 1 K is called specific heat capacity (c).
2. The specific heat capacity of a substance remains the same irrespective of the amount of mass of the substance taken.

Hence, the correct answer is (A) Both ‘A’ and ‘R’ are correct and ‘R’ is the correct explanation of ‘A’.