A large flask fitted with a stopcock is evacuated and weighted. Its mass is found to be 134.567 g. The volume of the flask was 500ml. It is then filled at a pressure of 735 mm and `131^(@)C` with a gas of unknown molecular mass and then reweighed. Its mass is 137.456 g. Assuming that the gas is ideal, calculate the molar mass of the gas.

Explanation

To solve the problem, we will follow these steps:

### Step 1: Determine the Mass of the Gas
First, we need to find the mass of the gas that was filled in the flask. This can be calculated by subtracting the mass of the empty flask from the mass of the flask filled with gas.

\[ \text{Mass of gas} = \text{Mass of flask with gas} - \text{Mass of empty flask} \]
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