Which of the following is an example of strong electrolyte?

Options

A. `NH_4 OH `solution
B. NaOH
C. `CH_3 COOH`
D. HCN

Explanation

To determine which of the given options is an example of a strong electrolyte, we can follow these steps:

### Step-by-Step Solution:

1. **Understand the Definition of Strong Electrolyte**:
A strong electrolyte is a substance that completely dissociates into its ions when dissolved in water. This means that 100% of the solute molecules break apart into their constituent ions.

2. **Identify the Given Substances**:
We need to analyze the substances provided in the options (for example: NH4OH, CH3COOH, HCN, NaOH).

3. **Analyze Each Substance**:
- **NH4OH (Ammonium Hydroxide)**: This is a weak electrolyte because it does not completely dissociate in solution. Only a fraction of the molecules ionize to form NH4⁺ and OH⁻ ions.
- **CH3COOH (Acetic Acid)**: This is also a weak electrolyte as it partially ionizes in solution, meaning not all molecules dissociate into ions.
- **HCN (Hydrogen Cyanide)**: This is another weak electrolyte, as it does not fully dissociate in solution.
- **NaOH (Sodium Hydroxide)**: This is a strong electrolyte because it completely dissociates into Na⁺ and OH⁻ ions when dissolved in water.

4. **Conclusion**:
Based on the analysis, the strong electrolyte among the options is **NaOH**.

### Final Answer:
The example of a strong electrolyte is **NaOH**.

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