Which of the following compounds is a strong electrolyte?

• A. C_6H_{12}O_6 (glucose)
• B. NH_3 (ammonia)
• C. NaCl (sodium chloride)
• D. CH_3COOH (acetic acid)

Answer: (C)

Verified step by step guidance

1. Understand what a strong electrolyte is: a substance that completely dissociates into ions when dissolved in water, resulting in a solution that conducts electricity very well.
2. Analyze each compound to determine if it dissociates fully into ions in aqueous solution:
3. C_6H_{12}O_6 (glucose) is a molecular compound that dissolves in water but does not ionize; it remains as neutral molecules, so it is a nonelectrolyte.
4. NH_3 (ammonia) is a weak base that partially ionizes in water, producing some ions but not completely, so it is a weak electrolyte.
5. NaCl (sodium chloride) is an ionic compound that dissociates completely into Na^{+} and Cl^{-} ions in water, making it a strong electrolyte.
6. CH_3COOH (acetic acid) is a weak acid that partially ionizes in water, so it is a weak electrolyte.