Question

When carbon dioxide is dissolved in an aqueous solution of sodium
hydroxide, the mixture reacts to yield aqueous sodium carbonate and liquid
water. Write balanced molecular, complete ionic, and net ionic equations for
this process.

Answer 1

When carbon dioxide (\( \text{CO}_2 \)) is dissolved in an aqueous solution of sodium hydroxide (\( \text{NaOH} \)), it reacts to form sodium carbonate (\( \text{Na}_2\text{CO}_3 \)) and water (\( \text{H}_2\text{O} \)).

### 1. Balanced Molecular Equation

To write the balanced molecular equation, we first identify the reactants and products:

\[
\text{CO}_2 (g) + 2 \text{NaOH} (aq) \rightarrow \text{Na}_2\text{CO}_3 (aq) + \text{H}_2\text{O} (l)
\]

### 2. Complete Ionic Equation

Next, we write the complete ionic equation. In this equation, we break all soluble strong electrolytes (like \( \text{NaOH} \) and \( \text{Na}_2\text{CO}_3 \)) into their respective ions:

\[
\text{CO}_2 (g) + 2 \text{Na}^+ (aq) + 2 \text{OH}^- (aq) \rightarrow 2 \text{Na}^+ (aq) + \text{CO}_3^{2-} (aq) + \text{H}_2\text{O} (l)
\]

### 3. Net Ionic Equation

To get the net ionic equation, we remove the spectator ions (ions that remain unchanged on both sides). In this case, the sodium ions (\( \text{Na}^+ \)) are spectators:

\[
\text{CO}_2 (g) + 2 \text{OH}^- (aq) \rightarrow \text{CO}_3^{2-} (aq) + \text{H}_2\text{O} (l)
\]

### Summary

- **Balanced Molecular Equation**:
\[
\text{CO}_2 (g) + 2 \text{NaOH} (aq) \rightarrow \text{Na}_2\text{CO}_3 (aq) + \text{H}_2\text{O} (l)
\]

- **Complete Ionic Equation**:
\[
\text{CO}_2 (g) + 2 \text{Na}^+ (aq) + 2 \text{OH}^- (aq) \rightarrow 2 \text{Na}^+ (aq) + \text{CO}_3^{2-} (aq) + \text{H}_2\text{O} (l)
\]

- **Net Ionic Equation**:
\[
\text{CO}_2 (g) + 2 \text{OH}^- (aq) \rightarrow \text{CO}_3^{2-} (aq) + \text{H}_2\text{O} (l)
\]