Write structural formula of 1-chlorobutan-2-one.

Explanation

To write the structural formula of 1-chlorobutan-2-one, follow these steps:

### Step 1: Identify the Carbon Chain
1. **Identify the base name**: The name "butan" indicates a four-carbon chain.
2. **Draw the carbon chain**: Start by drawing a straight chain of four carbon atoms.

```
C1 - C2 - C3 - C4
...