180 mL of a hydrocarbon diffuse through a porous membrane in 15 minutes, while 120 mL of `SO_2` under identical conditions diffuse in 20 minutes. What is the molecular mass of the hydrocarbon ?

Explanation

To find the molecular mass of the hydrocarbon using Graham's law of effusion, we can follow these steps:

### Step-by-Step Solution:

1. **Identify the Given Data:**
- Volume of hydrocarbon (V1) = 180 mL
- Time taken for hydrocarbon (T1) = 15 minutes
- Volume of SO₂ (V2) = 120 mL
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