Oxalic acid on being heated upto `90^(@)C` with conc. `H_(2)SO_(4)` forms

Options

A. `HCOOH+CO_(2)`
B. `CO_(2)+H_(2)O`
C. `CO_(2)+CO+H_(2)O`
D. `HCOOH+CO`

Explanation

To solve the question regarding the reaction of oxalic acid when heated with concentrated sulfuric acid, we can follow these steps:

### Step-by-Step Solution:

1. **Identify the Reactants**:
Oxalic acid has the chemical formula \( \text{C}_2\text{H}_2\text{O}_4 \) or can be represented as \( \text{HOOC-COOH} \).

2. **Understand the Role of Concentrated Sulfuric Acid**:
Concentrated sulfuric acid (\( \text{H}_2\text{SO}_4 \)) is a strong dehydrating agent. This means it can remove water from other substances.

3. **Heating Process**:
When oxalic acid is heated with concentrated sulfuric acid at \( 90^\circ C \), the heat and the dehydrating nature of sulfuric acid will facilitate the breakdown of oxalic acid.

4. **Dehydration Reaction**:
The dehydration process leads to the removal of water (\( \text{H}_2\text{O} \)) and results in the formation of gases. The reaction can be summarized as:
\[ \text{C}_2\text{H}_2\text{O}_4 \xrightarrow{\text{H}_2\text{SO}_4, \text{heat}} \text{CO}_2 + \text{CO} + \text{H}_2\text{O} \]

5. **Products of the Reaction**:
The products formed from this reaction are:
- Carbon dioxide (\( \text{CO}_2 \))
- Carbon monoxide (\( \text{CO} \))
- Water (\( \text{H}_2\text{O} \))

6. **Conclusion**:
Therefore, the final products when oxalic acid is heated with concentrated sulfuric acid at \( 90^\circ C \) are carbon dioxide, carbon monoxide, and water.

### Final Answer:
The products formed are \( \text{CO}_2 \), \( \text{CO} \), and \( \text{H}_2\text{O} \).

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