Which of the following forms metal oxide on heating

Options

A. `Na_(2)CO_(3)`
B. `Li_(2)CO_(3)`
C. `K_(2)SO_(4)`
D. `NaHCO_(3)`

Answer

To determine which of the given compounds forms a metal oxide upon heating, let's analyze each option step by step.

### Step 1: Identify the Compounds
The question provides four options, which are:
- A) Sodium Carbonate (Na2CO3)
- B) Lithium Carbonate (Li2CO3)
- C) Potassium Sulfate (K2SO4)
- D) Sodium Bicarbonate (NaHCO3)

### Step 2: Understand the Heating Process
When metal carbonates or bicarbonates are heated, they typically decompose to form metal oxides and release carbon dioxide (CO2) gas. The general reactions are:
- For carbonates:
\[ \text{M}_2\text{CO}_3 \rightarrow \text{M}_2\text{O} + \text{CO}_2 \uparrow \]
- For bicarbonates:
\[ \text{MHCO}_3 \rightarrow \text{MO} + \text{CO}_2 \uparrow + \text{H}_2\text{O} \]

### Step 3: Analyze Each Compound
1. **Sodium Carbonate (Na2CO3)**:
- Upon heating, it does not decompose to form Na2O; it remains stable.

2. **Lithium Carbonate (Li2CO3)**:
- Upon heating, it decomposes to form lithium oxide (Li2O) and carbon dioxide (CO2).
\[ \text{Li}_2\text{CO}_3 \rightarrow \text{Li}_2\text{O} + \text{CO}_2 \uparrow \]

3. **Potassium Sulfate (K2SO4)**:
- It does not decompose to form K2O upon heating; it remains stable.

4. **Sodium Bicarbonate (NaHCO3)**:
- Upon heating, it decomposes to form sodium oxide (Na2O), carbon dioxide (CO2), and water (H2O).
\[ 2\text{NaHCO}_3 \rightarrow \text{Na}_2\text{O} + 2\text{CO}_2 \uparrow + \text{H}_2\text{O} \]

### Step 4: Conclusion
From the analysis, we find that both **Lithium Carbonate (Li2CO3)** and **Sodium Bicarbonate (NaHCO3)** form metal oxides upon heating. However, since the question asks for which of the following forms a metal oxide, the most straightforward answer is:
- **B) Lithium Carbonate (Li2CO3)** is the most stable and directly forms a metal oxide.

### Final Answer
**B) Lithium Carbonate (Li2CO3)** is the correct option.

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