An organic compound X with molecular formula `C_(2)H_(4)O_(2)` turns litmus red and gives brisk effervescence with sodium bicarbonate. Identify the compound.

Options

A. Ethanol
B. Ethanoic acid
C. Ethanal
D. Ethyl ethanoate

Explanation

To identify the organic compound X with the molecular formula C₂H₄O₂, we can follow these steps:

### Step 1: Analyze the Molecular Formula
The molecular formula C₂H₄O₂ suggests that the compound contains 2 carbon atoms, 4 hydrogen atoms, and 2 oxygen atoms. This formula is characteristic of several organic compounds, but we need to consider the properties mentioned in the question.

**Hint 1:** Look for common organic compounds that match the molecular formula C₂H₄O₂.

### Step 2: Determine the Acidic Nature
The problem states that the compound turns blue litmus paper red. This indicates that the compound is acidic.

**Hint 2:** Recall that acids are substances that can donate protons (H⁺ ions) and will change the color of litmus paper.

### Step 3: Identify the Possible Compound
Given that the compound is acidic and has the formula C₂H₄O₂, the most likely candidate is acetic acid, also known as ethanoic acid (CH₃COOH).

**Hint 3:** Remember that acetic acid is a well-known weak acid that fits the molecular formula C₂H₄O₂.

### Step 4: Reaction with Sodium Bicarbonate
The compound also gives brisk effervescence with sodium bicarbonate (NaHCO₃). When an acid reacts with sodium bicarbonate, it produces carbon dioxide (CO₂) gas, which is responsible for the effervescence.

The reaction can be represented as:
\[ \text{CH}_3\text{COOH} + \text{NaHCO}_3 \rightarrow \text{CH}_3\text{COONa} + \text{H}_2\text{O} + \text{CO}_2 \uparrow \]

**Hint 4:** Consider the products formed in the reaction and how they relate to the properties of acids.

### Step 5: Conclusion
Based on the analysis, the compound X is identified as ethanoic acid (acetic acid).

**Final Answer:** The compound X is ethanoic acid (CH₃COOH).