Substance used in the preparation of carbon dioxide along with dil. HCl

Answer

To answer the question about the substance used in the preparation of carbon dioxide along with dilute hydrochloric acid, we can follow these steps:

### Step-by-Step Solution:

1. **Identify the Reaction**: We need to find a substance that reacts with dilute hydrochloric acid (HCl) to produce carbon dioxide (CO₂).

2. **Recall the Reaction of Acids with Carbonates**: It is known that carbonates react with acids to produce carbon dioxide, water, and a salt.

3. **Determine the Specific Carbonate**: One common carbonate that reacts with hydrochloric acid is calcium carbonate (CaCO₃).

4. **Write the Chemical Equation**: The reaction can be represented as:
\[ \text{CaCO}_3 (s) + 2 \text{HCl} (aq) \rightarrow \text{CaCl}_2 (aq) + \text{CO}_2 (g) + \text{H}_2O (l) \]
In this reaction, calcium carbonate reacts with dilute hydrochloric acid to produce calcium chloride, carbon dioxide, and water.

5. **Check the Balancing of the Equation**:
- On the reactant side: 1 calcium (Ca), 1 carbon (C), 3 oxygen (O), and 2 hydrogen (H) from HCl.
- On the product side: 1 calcium (Ca), 1 carbon (C), 3 oxygen (O) (2 from CO₂ and 1 from H₂O), and 2 hydrogen (H) from H₂O.
- The equation is balanced as the number of atoms of each element is the same on both sides.

6. **Conclusion**: The substance used for the preparation of carbon dioxide along with dilute hydrochloric acid is calcium carbonate (CaCO₃).

### Final Answer:
The substance used in the preparation of carbon dioxide along with dilute hydrochloric acid is **calcium carbonate (CaCO₃)**.

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