Carbon suboxide `C_3 O_2 (O = C=C=C=O)` is obtaind as a corlurless gas by the dehyration of malonic acid with .

Options

A. Caonc ` H_2 SO_4`
B. `H_2 PO_4`
C. `P_4O_(10)`
D. `All`

Explanation

To solve the question about obtaining carbon suboxide (C₃O₂) from malonic acid through dehydration, we can follow these steps:

### Step-by-Step Solution:

1. **Identify Malonic Acid Structure**:
- Malonic acid is a dicarboxylic acid with the formula HOOC-CH₂-COOH. It has two carboxyl (-COOH) groups attached to a central carbon atom.

2. **Write the Chemical Reaction**:
- The dehydration of malonic acid involves the removal of water (H₂O) molecules from the structure. The reaction can be represented as:
\[ \text{HOOC-CH}_2\text{-COOH} \xrightarrow{\text{P}_4\text{O}_{10}, \Delta} \text{C}_3\text{O}_2 + 2 \text{H}_2\text{O} \]
- Here, P₄O₁₀ (phosphorus pentoxide) acts as a dehydrating agent.

3. **Dehydration Process**:
- When malonic acid is heated in the presence of P₄O₁₀, it loses two molecules of water. This dehydration leads to the formation of carbon suboxide (C₃O₂), which has the structure O=C=C=C=O.

4. **Conditions for Reaction**:
- The reaction typically occurs at elevated temperatures, around 250 degrees Celsius, to facilitate the removal of water and promote the formation of carbon suboxide.

5. **Final Product**:
- The final product of this dehydration reaction is carbon suboxide (C₃O₂), along with the release of two water molecules.

### Final Answer:
Carbon suboxide (C₃O₂) is obtained by the dehydration of malonic acid using phosphorus pentoxide (P₄O₁₀) as a dehydrating agent at a temperature of 250 degrees Celsius.

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