A hydrocarbon of molecular mass 72 g `mol^(-1)` gives a single monochloro derivative and two dichloro derivatives on photo chlorination. Give the structure of the hydrocarbon.

Explanation

To solve the problem, we need to identify a hydrocarbon with a molecular mass of 72 g/mol that can produce one monochloro derivative and two dichloro derivatives upon photochlorination.

### Step-by-step Solution:

1. **Determine the Molecular Formula:**
- The molecular mass of the hydrocarbon is given as 72 g/mol.
- We need to consider hydrocarbons (compounds made of carbon and hydrogen) and find a suitable formula that fits this molecular weight.

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