Testing for carbonates (CO3^2-)

1 mark · Normal

Which observation indicates the presence of carbonate ions when dilute hydrochloric acid is added to a solid sample?

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Correct option: Effervescence (bubbles of gas) occurs

Common mistakes: choosing precipitate

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Marking points

B1 · 1 mark · Effervescence (bubbles) is the correct test result for carbonate with acid.

Worked solution

Adding acid to carbonate produces carbon dioxide gas, causing effervescence (option C).