Which gas is evolved when metal carbonates or metal hydrogencarbonate reacts with dilute acids ?

Explanation

To answer the question of which gas is evolved when metal carbonates or metal hydrogencarbonates react with dilute acids, we can follow these steps:

### Step-by-Step Solution:

1. **Identify the Reaction**: When metal carbonates (like sodium carbonate) or metal hydrogencarbonates (like sodium bicarbonate) react with dilute acids, a chemical reaction occurs.

2. **Recognize the Products**: The general reaction for a metal carbonate with a dilute acid can be written as:
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