Cuprous oxide dissolves in dilute sulfuric acid: Cu2O + 2H^+ -> Cu^2+ + Cu + H2O. The colour of the resulting solution and the spin-only magnetic moment of the copper cation in it are:

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Cuprous oxide dissolves in dilute sulfuric acid: $Cu X_{2} O + 2 H X^{+} Cu X^{2 +} + Cu + H X_{2} O$ . The colour of the resulting solution and the spin-only magnetic moment of the copper cation in it are:

The equation balances (2 Cu, 1 O, 2 H, charge +2). Cu(I) disproportionates into

Cu X^{2 +}

and Cu metal.

Cu X^{2 +}

3 d^{9}

with 1 unpaired electron (1.73 BM) and gives a blue aqueous solution.