For n moles of a gas, the difference between the molar heat capacity at constant pressure and that at constant volume is equal to `"…............."`.

Explanation

To solve the question regarding the difference between the molar heat capacity at constant pressure (Cp) and that at constant volume (Cv) for n moles of a gas, we can follow these steps:

### Step-by-Step Solution:

1. **Understand the Definitions**:
- Molar heat capacity at constant volume (Cv) is the amount of heat required to raise the temperature of one mole of a substance by one degree Celsius at constant volume.
- Molar heat capacity at constant pressure (Cp) is the amount of heat required to raise the temperature of one mole of a substance by one degree Celsius at constant pressure.

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