On heating calcium acetate and calcium formate, the product formed is :

Options

A. `CH_3 COCH_3`
B. `CH_3 CHO`
C. `HCHO + CaCO_3`
D. `CH_3 CHO + CaCO_3`

Explanation

To solve the question regarding the products formed on heating calcium acetate and calcium formate, we can follow these steps:

### Step-by-Step Solution:

1. **Identify the Compounds**:
- Calcium acetate has the formula \( \text{Ca(CH}_3\text{COO)}_2 \) which can be represented as \( \text{CH}_3\text{COO}^- \text{Ca}^{2+} \).
- Calcium formate has the formula \( \text{Ca(HCOO)}_2 \) which can be represented as \( \text{HCOO}^- \text{Ca}^{2+} \).

2. **Write the Structural Formulas**:
- Calcium acetate:
\[ \text{CH}_3\text{C(=O)O}^- \text{Ca}^{2+} \text{CH}_3\text{C(=O)O}^- \]
- Calcium formate:
\[ \text{HCOO}^- \text{Ca}^{2+} \text{HCOO}^- \]

3. **Heating the Compounds**:
- When heated, both calcium acetate and calcium formate undergo thermal decomposition. The carboxylate groups break down to form aldehydes and calcium carbonate.

4. **Decomposition Products**:
- From calcium acetate, we get acetaldehyde (\( \text{CH}_3\text{CHO} \)).
- From calcium formate, we also get acetaldehyde (\( \text{CH}_3\text{CHO} \)).
- Additionally, calcium carbonate (\( \text{CaCO}_3 \)) is formed as a byproduct.

5. **Final Products**:
- Therefore, the overall reaction can be summarized as:
\[ \text{Ca(CH}_3\text{COO)}_2 + \text{Ca(HCOO)}_2 \xrightarrow{\text{heat}} 2 \text{CH}_3\text{CHO} + 2 \text{CaCO}_3 \]

6. **Conclusion**:
- The products formed on heating calcium acetate and calcium formate are \( 2 \text{CH}_3\text{CHO} \) (which is acetaldehyde) and \( 2 \text{CaCO}_3 \) (calcium carbonate).

### Final Answer:
The correct answer is \( \text{CH}_3\text{CHO} + \text{CaCO}_3 \) (option D).

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