What is the chemical equation and explanation of the reaction between calcium carbonate and hydrochloric acid?

1 answer

The reaction between calcium carbonate (CaCO₃) and hydrochloric acid (HCl) can be represented by the following chemical equation:

\[ \text{CaCO}_3 (s) + 2 , \text{HCl} (aq) \rightarrow \text{CaCl}_2 (aq) + \text{H}_2\text{O} (l) + \text{CO}_2 (g) \]

Explanation of the Reaction:

  1. Reactants:

    • Calcium carbonate (CaCO₃) is a solid, commonly found in limestone and marble.
    • Hydrochloric acid (HCl) is an aqueous solution of a strong acid.
  2. Reaction Process:

    • When calcium carbonate is added to hydrochloric acid, it begins to react. The acid donates protons (H⁺) to the carbonate ions (CO₃²⁻) present in calcium carbonate.
    • This reaction produces calcium chloride (CaCl₂), water (H₂O), and carbon dioxide (CO₂).
  3. Products:

    • Calcium chloride (CaCl₂): This is a soluble salt that remains dissolved in the aqueous solution.
    • Water (H₂O): This is produced as part of the neutralization process.
    • Carbon dioxide (CO₂): This gas is released in bubbles, which can be observed as effervescence during the reaction.

Observations:

  • You will notice bubbling or fizzing due to the liberation of carbon dioxide gas.
  • The solid calcium carbonate will gradually dissolve as it reacts with the acid.

Conclusion:

This reaction is an example of an acid-carbonate reaction, where an acid reacts with a carbonate to produce a salt, water, and carbon dioxide gas. It is often used to demonstrate acid-base reactions in chemistry.