Same chapter3 marksDifficulty: Medium
A white precipitate is formed when sodium hydroxide is added to a salt solution, and it does not dissolve in excess. Name the cation and state one further test.
Analytical Chemistry
3 marksDifficulty: Medium
How would you distinguish between a solution of iron(II) sulphate and one of iron(III) chloride using sodium hydroxide solution?
Original Khojo Papers practice question — not from a past board paper.
Answer
Iron(II) sulphate gives a dirty green precipitate of iron(II) hydroxide, while iron(III) chloride gives a reddish-brown precipitate of iron(III) hydroxide. Neither dissolves in excess alkali.
No citable source has been recorded for this record. Treat it as practice material, not as fact.
Explanation
The colour of the precipitate is the whole of the test.
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