Question

What is the complete ionic and net ionic equation for CaCl2(aq) and K2SO4(aq)?

Answer 1

To determine the complete ionic and net ionic equations for the reaction between calcium chloride (CaCl₂) and potassium sulfate (K₂SO₄), we first need to write down the balanced molecular equation for the reaction:

\[ \text{CaCl}_2(aq) + \text{K}_2\text{SO}_4(aq) \rightarrow \text{CaSO}_4(s) + 2 \text{KCl}(aq) \]

### Step 1: Complete Ionic Equation

For the complete ionic equation, we need to break down the soluble ionic compounds into their ions.

The solubility rules tell us that both CaCl₂ and K₂SO₄ are soluble in water, so they will dissociate completely in aqueous solution:

\[
\text{Ca}^{2+}(aq) + 2 \text{Cl}^-(aq) + 2 \text{K}^+(aq) + \text{SO}_4^{2-}(aq) \rightarrow \text{CaSO}_4(s) + 2 \text{K}^+(aq) + 2 \text{Cl}^-(aq)
\]

### Step 2: Net Ionic Equation

To write the net ionic equation, we eliminate the spectator ions, which are ions that appear on both sides of the complete ionic equation. In this case, \( \text{K}^+ \) and \( \text{Cl}^- \) are the spectator ions:

The spectator ions:

- \( 2 \text{K}^+(aq) \)
- \( 2 \text{Cl}^-(aq) \)

Removing these from the complete ionic equation gives us the net ionic equation:

\[
\text{Ca}^{2+}(aq) + \text{SO}_4^{2-}(aq) \rightarrow \text{CaSO}_4(s)
\]

### Summary of Equations

- **Molecular Equation**:
\[
\text{CaCl}_2(aq) + \text{K}_2\text{SO}_4(aq) \rightarrow \text{CaSO}_4(s) + 2 \text{KCl}(aq)
\]

- **Complete Ionic Equation**:
\[
\text{Ca}^{2+}(aq) + 2 \text{Cl}^-(aq) + 2 \text{K}^+(aq) + \text{SO}_4^{2-}(aq) \rightarrow \text{CaSO}_4(s) + 2 \text{K}^+(aq) + 2 \text{Cl}^-(aq)
\]

- **Net Ionic Equation**:
\[
\text{Ca}^{2+}(aq) + \text{SO}_4^{2-}(aq) \rightarrow \text{CaSO}_4(s)
\]