A vessel with small opening contained equal volumes of oxygen and an unknown gas. Oxygen effused through the opening 1.8 times faster than the unknown gas. If the atomic mass of oxygen is 16, calculate the molecular mass of the unknown gas.

Explanation

To solve the problem, we will use Graham's law of effusion, which states that the rate of effusion of a gas is inversely proportional to the square root of its molecular mass.

### Step-by-Step Solution:

1. **Identify the Given Information:**
- The rate of effusion of oxygen (O₂) is 1.8 times the rate of effusion of the unknown gas (let's denote it as gas X).
- The atomic mass of oxygen is 16 g/mol, so the molecular mass of O₂ (which is diatomic) is:
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