Question

which electrolyte is used in an alkali fuel cell?
○ a high temperature carbonate salt mixture
○ a solid polymer
○ a solid ceramic metal oxide compound
○ an aqueous potassium hydroxide solution

Explanation:

Alkali fuel cells (AFCs) use an aqueous potassium hydroxide (KOH) solution as the electrolyte. High - temperature carbonate salt mixtures are used in molten carbonate fuel cells, solid polymers are used in polymer electrolyte membrane fuel cells, and solid ceramic metal oxide compounds are used in solid - oxide fuel cells.

Answer:

an aqueous potassium hydroxide solution