Which of the following metal carbonates liberate. `CO_(2)(g)` on heating :

Options

A. `Na_(2)CO_(3)`
B. `K_(2)CO_(3)`
C. `Rb_(2)CO_(3)`
D. `Ag_(2)CO_(3)`

Answer

To determine which metal carbonates liberate carbon dioxide gas (CO₂) upon heating, we can follow these steps:

### Step 1: Identify the metal carbonates in the options
First, we need to identify the metal carbonates provided in the question. Common metal carbonates include those of sodium (Na), potassium (K), rubidium (Rb), cesium (Cs), and silver (Ag).

### Step 2: Understand the decomposition of metal carbonates
When heated, not all metal carbonates decompose to release carbon dioxide. Generally, the carbonates of alkali metals (like sodium, potassium, rubidium, and cesium) do not decompose upon heating. However, some transition metal carbonates, such as silver carbonate, do decompose.

### Step 3: Analyze the behavior of each carbonate
- **Sodium carbonate (Na₂CO₃)**: Does not decompose on heating.
- **Potassium carbonate (K₂CO₃)**: Does not decompose on heating.
- **Rubidium carbonate (Rb₂CO₃)**: Does not decompose on heating.
- **Cesium carbonate (Cs₂CO₃)**: Does not decompose on heating.
- **Silver carbonate (Ag₂CO₃)**: Decomposes upon heating to form silver oxide (Ag₂O) and releases carbon dioxide (CO₂).

### Step 4: Conclude the results
From the analysis, we can conclude that among the given options, only silver carbonate (Ag₂CO₃) liberates carbon dioxide gas upon heating.

### Final Answer:
The metal carbonate that liberates CO₂ on heating is **Silver Carbonate (Ag₂CO₃)**.

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