An organic compound B has the molecular formula `C_2H_4O_2`. It reacts with sodium hydrogen carbonate to produce a gas and salt, the gas turns lime water milky.
What is the IUPAC name of B?

Explanation

To determine the IUPAC name of the organic compound B with the molecular formula C₂H₄O₂, follow these steps:

### Step 1: Analyze the Molecular Formula
The molecular formula given is C₂H₄O₂. This indicates that the compound contains 2 carbon atoms, 4 hydrogen atoms, and 2 oxygen atoms.

### Step 2: Identify Possible Structures
Given the molecular formula, we can deduce that the compound could be an acid, an ester, or an alcohol. However, the reaction with sodium hydrogen carbonate suggests that it is likely an acid, as acids typically react with bicarbonates to produce carbon dioxide gas.

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