A pink coloured salt turns blue on heating. The presence of which cation is most likely ?
Show Hint
- \(\mathrm{Cu^{2+}}\)
- \(\mathrm{Fe^{2+}}\)
- \(\mathrm{Zn^{2+}}\)
- \(\mathrm{Co^{2+}}\)
The Correct Option is D
Solution and Explanation
Cu2+ salts are blue/green when hydrated and turn white on dehydration; Fe2+ salts are pale green; Zn2+ salts are colourless/white.
Answer: (4) Co2+
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