The number of structurally isomeric esters with molecular formula `C_(5H_(10)O2` are.

Explanation

To determine the number of structurally isomeric esters with the molecular formula C5H10O2, we will follow these steps:

### Step 1: Understand the Structure of Esters
Esters have the general structure RCOOR', where R and R' are hydrocarbon chains. The presence of the carbonyl group (C=O) and the ether-like linkage (C-O) is crucial in defining the ester.

### Step 2: Identify the Molecular Formula
The given molecular formula is C5H10O2. This indicates that there are 5 carbon atoms, 10 hydrogen atoms, and 2 oxygen atoms in the ester.

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