Which of the following is a nonelectrolyte? Please state why or why not for each. Thanks
a) NaOH
b) HNO3
c) C2H6O (ethanol)
d) KF
e) CH3COOH (acetic acid)
The Correct Answer and Explanation is:
The correct answer is: c) C₂H₆O (ethanol)
Explanation (300+ words):
To determine which substance is a nonelectrolyte, we need to understand what an electrolyte is. An electrolyte is a substance that dissolves in water and produces ions, allowing the solution to conduct electricity. There are three main categories:
- Strong electrolytes – completely dissociate into ions (e.g., NaOH, HNO₃, KF).
- Weak electrolytes – partially dissociate into ions (e.g., CH₃COOH).
- Nonelectrolytes – do not dissociate into ions in solution and therefore do not conduct electricity (e.g., ethanol).
Let’s evaluate each option:
a) NaOH (sodium hydroxide)
- Type: Strong base, strong electrolyte
- Why: Dissociates completely into Na⁺ and OH⁻ ions in water.
- Conclusion: Not a nonelectrolyte
b) HNO₃ (nitric acid)
- Type: Strong acid, strong electrolyte
- Why: Fully ionizes in water to form H⁺ and NO₃⁻ ions.
- Conclusion: Not a nonelectrolyte
c) C₂H₆O (ethanol)
- Type: Covalent compound, nonelectrolyte
- Why: Although ethanol dissolves well in water due to hydrogen bonding, it does not ionize. No ions = no electrical conductivity.
- Conclusion: ✅ Correct answer: Nonelectrolyte
d) KF (potassium fluoride)
- Type: Ionic compound, strong electrolyte
- Why: Dissolves in water to give K⁺ and F⁻ ions, conducting electricity well.
- Conclusion: Not a nonelectrolyte
e) CH₃COOH (acetic acid)
- Type: Weak acid, weak electrolyte
- Why: Partially ionizes in water to produce some H⁺ and CH₃COO⁻, so it conducts electricity weakly.
- Conclusion: Not a nonelectrolyte
Summary:
Among the given options, only ethanol (C₂H₆O) is a nonelectrolyte because it does not dissociate into ions in solution, and therefore does not conduct electricity. All the others either strongly or weakly ionize in water, qualifying them as electrolytes.