Reactions of acids
2 marks · EasyExplain, in terms of proton transfer, why hydrochloric acid acts as an acid when it reacts with potassium hydroxide.
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Hydrochloric acid acts as an acid because it donates a proton (H⁺) to potassium hydroxide, which accepts the proton.
Also accept: HCl donates a proton to KOH; KOH accepts a proton from HCl
Common mistakes: acid accepts a proton; potassium hydroxide donates a proton
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Marking points
M1 · 1 mark · Identifies HCl as a proton donor (acid).
A1 · 1 mark · States that KOH accepts the proton (is a base).
Worked solution
Hydrochloric acid acts as an acid because it donates a proton (H⁺) to potassium hydroxide.
Potassium hydroxide acts as a base because it accepts the proton.