At `27^(@)C`, hydrogen is leaked through a tiny hole into a vessel for `20 min`. Another unknown gas at the same temperature and pressure as that of hydrogen is leaked through the same hole for `20 min`. After the effusion of the gases, the mixture exerts a pressure of `6 atm`. The hydrogen content of the mixture is `0.7 mol`. If the volume of the container is `3 L`, what is the molecular weight of the unknown gas?

Explanation

To solve the problem, we can follow these steps:

### Step 1: Understand the Given Information
We know the following:
- Temperature (T) = 27°C = 300 K (after converting to Kelvin)
- Pressure of the gas mixture (P) = 6 atm
- Volume of the container (V) = 3 L
- Moles of hydrogen (n_H2) = 0.7 mol
...