An evacuated glass vessel weighs `50.0 g` when empty, `148.0 g` when filled with a liquid of density `0.98 g mL^(-1)`, and `50.5 g` when filled with an ideal gas at `760 mm Hg` at `300 K`. Determine the molar mass of the gas.

Explanation

To determine the molar mass of the gas in the evacuated glass vessel, we will follow these steps:

### Step 1: Calculate the mass of the liquid
The mass of the empty glass vessel is given as 50.0 g. When filled with the liquid, the mass is 148.0 g. Therefore, the mass of the liquid can be calculated as follows:

\[ \text{Mass of liquid} = \text{Mass of filled vessel} - \text{Mass of empty vessel} \]
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