Write down structure of the following compounds:
2-butenoic acid

Explanation

To draw the structure of 2-butenoic acid, we will follow these steps:

### Step 1: Identify the base name and the number of carbon atoms
- The name "butenoic acid" indicates that the compound has a butene structure, which means it contains 4 carbon atoms (but- = 4).
- The "enoic" part indicates that there is a double bond present in the structure.

**Hint:** The prefix "but-" indicates the number of carbon atoms in the longest chain.

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