SiO2 is reacted with sodium carbonate. What is the gas liberated?

Explanation

To determine the gas liberated when SiO2 reacts with sodium carbonate (Na2CO3), we can follow these steps:

### Step-by-Step Solution:

1. **Identify the Reactants**: The reactants in this reaction are silicon dioxide (SiO2) and sodium carbonate (Na2CO3).

2. **Write the Reaction**: When SiO2 reacts with Na2CO3, the reaction can be represented as:
\[ \text{SiO}_2 + \text{Na}_2\text{CO}_3 \rightarrow \text{Na}_2\text{SiO}_3 + \text{CO}_2 \]
Here, sodium silicate (Na2SiO3) is formed along with carbon dioxide (CO2) gas.

3. **Identify the Products**: The products of the reaction are sodium silicate (Na2SiO3) and carbon dioxide (CO2).

4. **Determine the Gas Liberated**: From the balanced equation, it is clear that the gas liberated during this reaction is carbon dioxide (CO2).

### Final Answer:
The gas liberated when SiO2 reacts with sodium carbonate is carbon dioxide (CO2).

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