NCERT In-text Q3 (Section 1.2.3) - Chemical Reactions and Equations
Question: Why does the colour of copper sulphate solution change when an iron nail is dipped in it?
Answer: Iron displaces copper from copper sulphate in a displacement reaction: Fe(s) + CuSO4(aq) → FeSO4(aq) + Cu(s). The blue colour fades (CuSO4 → FeSO4 pale green), and reddish-brown copper deposits on ...
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