Which of the following pairs of compounds are both electrolytes?

• A. C_6H_{12}O_6 and CH_3OH
• B. NaCl and HCl
• C. CO_2 and O_2
• D. C_2H_5OH and CCl_4

Answer: (B)

Verified step by step guidance

1. Understand what an electrolyte is: an electrolyte is a substance that dissociates into ions when dissolved in water, allowing the solution to conduct electricity.
2. Analyze each compound pair to determine if they produce ions in aqueous solution. For example, NaCl is an ionic compound that dissociates into Na⁺ and Cl⁻ ions, and HCl is a strong acid that ionizes completely into H⁺ and Cl⁻ ions.
3. Check the other pairs: C₆H₁₂O₆ (glucose) and CH₃OH (methanol) are molecular compounds that do not ionize significantly in water, so they are nonelectrolytes.
4. CO₂ and O₂ are gases and molecular compounds that do not ionize in water, so they are nonelectrolytes as well.
5. C₂H₅OH (ethanol) and CCl₄ (carbon tetrachloride) are molecular compounds; ethanol is a weak electrolyte but mostly nonelectrolyte, and CCl₄ is nonpolar and does not ionize, so this pair is not both electrolytes.