Write the molecular/chemical reaction of calcium carbonate with acetic acid and the net ionic equation.
The Correct Answer and Explanation is:
The reaction between calcium carbonate (CaCO₃) and acetic acid (CH₃COOH) is a classic acid-base reaction. Acetic acid, being a weak acid, reacts with calcium carbonate, which is a basic compound, to form calcium acetate (Ca(CH₃COO)₂), carbon dioxide (CO₂), and water (H₂O).
Molecular Reaction:
CaCO₃ (s)+2CH₃COOH (aq)→Ca(CH₃COO)₂ (aq)+CO₂ (g)+H₂O (l)\text{CaCO₃ (s)} + 2\text{CH₃COOH (aq)} \rightarrow \text{Ca(CH₃COO)₂ (aq)} + \text{CO₂ (g)} + \text{H₂O (l)}CaCO₃ (s)+2CH₃COOH (aq)→Ca(CH₃COO)₂ (aq)+CO₂ (g)+H₂O (l)
In this reaction:
- Calcium carbonate (CaCO₃) is a solid that reacts with acetic acid (CH₃COOH), which is dissolved in water (aqueous state).
- Calcium acetate (Ca(CH₃COO)₂) is formed in the solution, which is a soluble salt.
- Carbon dioxide (CO₂) is released as a gas, and water (H₂O) is formed.
Net Ionic Equation:
To write the net ionic equation, we first need to break down the molecular equation into ions. However, calcium carbonate is a solid and does not dissociate into ions. So, the ionic equation will look like this:
- Write the ionic equation:
CaCO₃ (s)+2CH₃COOH (aq)→Ca2+(aq)+2CH₃COO−(aq)+CO₂ (g)+H₂O (l)\text{CaCO₃ (s)} + 2\text{CH₃COOH (aq)} \rightarrow \text{Ca}^{2+} (aq) + 2\text{CH₃COO}^- (aq) + \text{CO₂ (g)} + \text{H₂O (l)}CaCO₃ (s)+2CH₃COOH (aq)→Ca2+(aq)+2CH₃COO−(aq)+CO₂ (g)+H₂O (l)
- Eliminate spectator ions (if any):
In this case, the calcium ions and acetate ions are directly involved in the reaction and no spectator ions are present, so the net ionic equation is the same as the ionic equation. - The net ionic equation:
CaCO₃ (s)+2CH₃COOH (aq)→Ca2+(aq)+2CH₃COO−(aq)+CO₂ (g)+H₂O (l)\text{CaCO₃ (s)} + 2\text{CH₃COOH (aq)} \rightarrow \text{Ca}^{2+} (aq) + 2\text{CH₃COO}^- (aq) + \text{CO₂ (g)} + \text{H₂O (l)}CaCO₃ (s)+2CH₃COOH (aq)→Ca2+(aq)+2CH₃COO−(aq)+CO₂ (g)+H₂O (l)
Explanation:
- Calcium carbonate (CaCO₃) reacts with acetic acid (CH₃COOH) to form calcium ions (Ca²⁺) and acetate ions (CH₃COO⁻) in solution.
- The CO₃²⁻ ions from calcium carbonate combine with H⁺ ions from acetic acid to produce CO₂ gas.
- The reaction produces water as the hydrogen ions (H⁺) from the acid combine with the carbonate ions (CO₃²⁻) to form H₂O.
This reaction is commonly observed when calcium carbonate is dissolved in vinegar (which contains acetic acid), such as when a shell (which is made of calcium carbonate) is placed in vinegar.
