In a Regnault's experiment, the mass of a definite volume of a gas was found to be 4.6420 g, whereas the mass of the same volume of hydrogen at the same temperature and pressure was found to be 0.2902 g. Calculate the vapour density and molecular mass of the gas.

Explanation

To solve the problem, we need to calculate the vapor density and molecular mass of the gas using the data provided in the Regnault's experiment.

### Step-by-Step Solution:

1. **Identify the Mass of the Gas and Hydrogen:**
- Mass of the gas (X) = 4.6420 g
- Mass of the same volume of hydrogen = 0.2902 g

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