Ideal Gas Equation

Dalton's law of partial pressures is not applicable when gas react under the experimental conditions. As and HCl readily react under ordinary conditions, Dalton's law of partial pressure is not applicable to this mixture.

Step 1: Understanding the Concept:
is molar heat capacity at constant pressure, and is molar heat capacity at constant volume. For an ideal gas, they are related via the gas constant .
Step 2: Key Formula or Approach:
The relation is known as Mayer’s relation: Step 3: Detailed Explanation:
Heat added at constant volume increases internal energy only.
Heat added at constant pressure increases internal energy AND does expansion work ( ).
For 1 mole of an ideal gas, .
Thus, .
Dividing by gives .
Step 4: Final Answer:
The correct relation is .