Sodium carbonate is a basic salt because it is a salt of a:

Options

A. strong acid and strong base
B. weak acid and weak base
C. strong acid and weak base
D. weak acid and strong base

Explanation

To determine why sodium carbonate (Na2CO3) is classified as a basic salt, we need to analyze the components that form this salt.

### Step-by-Step Solution:

1. **Identify the Components of Sodium Carbonate**:
Sodium carbonate is composed of sodium ions (Na⁺) and carbonate ions (CO3²⁻).

2. **Identify the Source of Sodium Ions**:
Sodium ions come from sodium hydroxide (NaOH), which is a strong base.

3. **Identify the Source of Carbonate Ions**:
The carbonate ion (CO3²⁻) is derived from carbonic acid (H2CO3), which is a weak acid.

4. **Understand the Reaction**:
Sodium carbonate is formed by the neutralization reaction between a strong base (NaOH) and a weak acid (H2CO3):
\[ 2 \text{NaOH} + \text{H}_2\text{CO}_3 \rightarrow \text{Na}_2\text{CO}_3 + 2 \text{H}_2\text{O} \]

5. **Determine the Nature of the Salt**:
Since sodium carbonate is formed from a strong base and a weak acid, it exhibits basic properties in solution. This is because the strong base completely dissociates and the weak acid does not fully dissociate, leading to an excess of hydroxide ions (OH⁻) in the solution.

6. **Conclusion**:
Therefore, sodium carbonate is classified as a basic salt because it is the salt of a strong base (NaOH) and a weak acid (H2CO3).

### Final Answer:
Sodium carbonate is a basic salt because it is a salt of a strong base and a weak acid.

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