Write down structure of the following compounds:
1-penten-3-one

Explanation

To write down the structure of the compound 1-penten-3-one, we will follow these steps:

### Step 1: Identify the number of carbon atoms
The name "pent" indicates that there are 5 carbon atoms in the compound.

### Step 2: Determine the position of the double bond
The "1" in "1-penten" indicates that there is a double bond starting at the first carbon atom.

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