Decomposition of oxalic acid in the presence of conc ` H-2 SO_4` gives :

Options

A. `CO`
B. `CO_2`
C. Formic acid
D. `H_2O`

Explanation

To solve the question regarding the decomposition of oxalic acid in the presence of concentrated sulfuric acid, we can follow these steps:

### Step 1: Understand the Reactants
- **Oxalic Acid (H₂C₂O₄)**: This is a dicarboxylic acid that can decompose under certain conditions.
- **Concentrated Sulfuric Acid (H₂SO₄)**: This is a strong acid and a dehydrating agent, meaning it can remove water from other substances.

**Hint**: Identify the chemical nature of the reactants involved in the reaction.

### Step 2: Identify the Reaction Conditions
- When oxalic acid is heated with concentrated sulfuric acid, the sulfuric acid acts as a dehydrating agent, facilitating the breakdown of oxalic acid.

**Hint**: Consider the role of concentrated sulfuric acid in the reaction.

### Step 3: Write the Decomposition Reaction
- The decomposition of oxalic acid can be represented as follows:
\[ H_2C_2O_4 \xrightarrow{H_2SO_4} CO + CO_2 + H_2O \]
- This indicates that oxalic acid decomposes to produce carbon monoxide (CO), carbon dioxide (CO₂), and water (H₂O).

**Hint**: Focus on the products formed during the decomposition process.

### Step 4: Identify the Products
- From the reaction, we can clearly see that the products formed are:
- Carbon monoxide (CO)
- Carbon dioxide (CO₂)
- Water (H₂O)

**Hint**: List out the products to confirm your understanding of the decomposition reaction.

### Step 5: Conclusion
- Therefore, the decomposition of oxalic acid in the presence of concentrated sulfuric acid results in the formation of carbon monoxide, carbon dioxide, and water.

**Final Answer**: The decomposition of oxalic acid in the presence of concentrated sulfuric acid gives carbon monoxide (CO), carbon dioxide (CO₂), and water (H₂O).

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