Which of the following is a nonelectrolyte? Please state why or why not for each.
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).
Here’s the explanation for each option:
a) NaOH (Sodium Hydroxide)
NaOH is an electrolyte. It dissociates completely in water into sodium ions (Na⁺) and hydroxide ions (OH⁻), which are free to move in the solution. This free movement of charged particles allows the solution to conduct electricity. Thus, NaOH is classified as a strong electrolyte because it completely dissociates in water.
b) HNO3 (Nitric Acid)
HNO3 is an electrolyte. It is a strong acid and dissociates completely in water into hydrogen ions (H⁺) and nitrate ions (NO₃⁻). As a result, it also conducts electricity when dissolved in water. Since HNO3 dissociates fully, it is considered a strong electrolyte.
c) C2H6O (Ethanol)
C2H6O, or ethanol, is a nonelectrolyte. It does not dissociate into ions in water, which is the defining characteristic of electrolytes. Ethanol dissolves in water and forms hydrogen bonds, but it remains as whole ethanol molecules (C2H6O) in solution. Since it does not produce ions, ethanol cannot conduct electricity in solution, making it a nonelectrolyte.
d) KF (Potassium Fluoride)
KF is an electrolyte. It dissociates into potassium ions (K⁺) and fluoride ions (F⁻) in water. The presence of these free ions in the solution allows it to conduct electricity. As KF dissociates completely, it is classified as a strong electrolyte.
e) CH3COOH (Acetic Acid)
CH3COOH is an electrolyte, but it is a weak electrolyte. While acetic acid does dissociate in water, it does so only partially. The dissociation results in the formation of hydrogen ions (H⁺) and acetate ions (CH₃COO⁻), but the equilibrium favors the undissociated acetic acid molecules. Thus, it conducts electricity to a lesser extent compared to strong electrolytes like NaOH or HNO3.
Conclusion
Ethanol (C2H6O) is the nonelectrolyte because it does not dissociate into ions in solution, unlike the other substances listed, which are all electrolytes in some form.