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:
To determine which substance is a nonelectrolyte, we must first understand what an electrolyte is. An electrolyte is a substance that dissolves in water to produce ions, allowing the solution to conduct electricity. Electrolytes can be strong (completely dissociate into ions) or weak (partially dissociate). In contrast, a nonelectrolyte dissolves in water without forming ions, so the solution does not conduct electricity.
Let’s analyze each option:
a) NaOH (sodium hydroxide)
Electrolyte: Yes (Strong)
NaOH is a strong base and completely dissociates in water:
NaOH → Na⁺ + OH⁻
Because it releases ions, it conducts electricity very well.
→ Not a nonelectrolyte.
b) HNO₃ (nitric acid)
Electrolyte: Yes (Strong)
HNO₃ is a strong acid and fully ionizes in water:
HNO₃ → H⁺ + NO₃⁻
Since it forms ions, it’s a strong electrolyte.
→ Not a nonelectrolyte.
c) C₂H₆O (ethanol)
Electrolyte: No (Nonelectrolyte)
Ethanol is an organic alcohol. It dissolves well in water due to hydrogen bonding, but it does not ionize in solution.
It remains as neutral ethanol molecules:
C₂H₆O (ethanol) ⇌ C₂H₆O (ethanol)
No ions are produced, so it does not conduct electricity.
→ This is the correct nonelectrolyte.
d) KF (potassium fluoride)
Electrolyte: Yes (Strong)
KF is an ionic compound that dissociates completely in water:
KF → K⁺ + F⁻
Ions are formed, and the solution conducts electricity.
→ Not a nonelectrolyte.
e) CH₃COOH (acetic acid)
Electrolyte: Yes (Weak)
Acetic acid is a weak acid. It only partially ionizes in water:
CH₃COOH ⇌ H⁺ + CH₃COO⁻
Though only a small portion ionizes, it still produces ions.
→ Not a nonelectrolyte.
Summary:
Only ethanol (C₂H₆O) is a nonelectrolyte because it dissolves in water without producing ions, thus does not conduct electricity. All others are electrolytes because they produce ions—either strongly or weakly—in aqueous solutions.