Sodium chloride reacts with copper sulfate to produce sodium sulfate and copper chloride.

[tex]\[ 2 \text{NaCl} ( \text{aq} ) + \text{CuSO}_4( \text{aq} ) \rightarrow \text{Na}_2 \text{SO}_4( \text{aq} ) + \text{CuCl}_2( \text{s} ) \][/tex]

This equation represents a:
A. synthesis reaction
B. decomposition reaction
C. single replacement reaction
D. double replacement reaction



Answer :

Sure, let's analyze the given chemical reaction step-by-step to determine its type.

The balanced chemical equation provided is:

[tex]\[ 2 \text{NaCl (aq)} + \text{CuSO}_4 \text{(aq)} \rightarrow \text{Na}_2 \text{SO}_4 \text{(aq)} + \text{CuCl}_2 \text{(s)} \][/tex]

First, let's break down the components involved:
- [tex]\( \text{NaCl} \)[/tex] is sodium chloride.
- [tex]\( \text{CuSO}_4 \)[/tex] is copper(II) sulfate.
- [tex]\( \text{Na}_2 \text{SO}_4 \)[/tex] is sodium sulfate.
- [tex]\( \text{CuCl}_2 \)[/tex] is copper(II) chloride.

Now, we need to classify the reaction by examining the changes taking place.

### Step-by-Step Analysis:
1. Reactants and Products Identification:
- Reactants: [tex]\( 2 \text{NaCl (aq)} \)[/tex] and [tex]\( \text{CuSO}_4 \text{(aq)} \)[/tex].
- Products: [tex]\( \text{Na}_2 \text{SO}_4 \text{(aq)} \)[/tex] and [tex]\( \text{CuCl}_2 \text{(s)} \)[/tex].

2. Exchange of Ions:
- In the reactants, sodium ([tex]\( \text{Na}^+ \)[/tex]) is paired with chloride ([tex]\( \text{Cl}^- \)[/tex]), and copper ([tex]\( \text{Cu}^{2+} \)[/tex]) is paired with sulfate ([tex]\( \text{SO}_4^{2-} \)[/tex]).
- In the products, sodium is now paired with sulfate to form [tex]\( \text{Na}_2 \text{SO}_4 \)[/tex], and copper is now paired with chloride to form [tex]\( \text{CuCl}_2 \)[/tex].

3. Type of Reaction:
- Sodium ([tex]\( \text{Na} \)[/tex]) and copper ([tex]\( \text{Cu} \)[/tex]) are essentially exchanging their anions ([tex]\( \text{Cl} \)[/tex] and [tex]\( \text{SO}_4 \)[/tex], respectively).

Such an exchange in which two compounds react, and the cations and anions switch places to form two new compounds, is classified as a double replacement reaction.

### Conclusion:
Considering the explanation and the given chemical reaction, this is indeed a double replacement reaction.

So, the correct answer is:
double replacement reaction.