In an experiment,` 4.5` mol of calcium carbonate are reacted with dilute hydrochloric acid.
Write the equation for the reaction.

Explanation

To write the equation for the reaction between calcium carbonate and dilute hydrochloric acid, follow these steps:

### Step-by-Step Solution:

1. **Identify the Reactants**:
- The first reactant is calcium carbonate, which has the chemical formula \( \text{CaCO}_3 \).
- The second reactant is hydrochloric acid, which has the chemical formula \( \text{HCl} \).

2. **Write the Balanced Chemical Equation**:
- When calcium carbonate reacts with hydrochloric acid, it produces calcium chloride, carbon dioxide, and water.
- The balanced chemical equation for the reaction is:
\[ \text{CaCO}_3 (s) + 2 \text{HCl} (aq) \rightarrow \text{CaCl}_2 (aq) + \text{CO}_2 (g) + \text{H}_2\text{O} (l) \]

### Final Answer:
The balanced equation for the reaction between calcium carbonate and dilute hydrochloric acid is:
\[ \text{CaCO}_3 (s) + 2 \text{HCl} (aq) \rightarrow \text{CaCl}_2 (aq) + \text{CO}_2 (g) + \text{H}_2\text{O} (l) \]

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