Write down structure of the following compounds:
Butenedioic acid

Explanation

To draw the structure of butenedioic acid, we will follow these steps:

### Step 1: Identify the Components of the Name
The name "butenedioic acid" can be broken down into parts:
- "Butene" indicates a four-carbon chain (but- refers to four carbons).
- "Di" indicates that there are two functional groups.
- "Oic acid" indicates that the functional groups are carboxylic acids (–COOH).
- "Ene" indicates that there is a double bond between two carbon atoms.
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