The number of structural isomers that are carboxylic acids with the formula C4H8O2 is A - VCE - SSCE Chemistry - Question 9 - 2006 - Paper 1

To find the structural isomers of carboxylic acids with the formula C4H8O2, we first need to recognize that carboxylic acids contain a carboxyl functional group (-COOH).

Next, the general structure of a carboxylic acid can be represented as:

$R - COOH$

Where R represents the hydrocarbon chain. For C4H8O2, we have different arrangements of carbon atoms within the structure.

The possible structural isomers can be drawn as follows:

1. Butanoic acid: A straight-chain carboxylic acid.
2. Isobutyric acid: A branched-chain carboxylic acid.

Thus, there are 2 distinct structural isomers of carboxylic acids with the formula C4H8O2.