Question

Which of the following statements regarding copper salts is not true?

• A. Copper (I) dispropotionates to copper and copper (II) ion in aqueous solution
• B. Copper (I) can be stabilised by the formation of insoluble complex compounds such as $Cu{Cl}_2^{-}$ and $Cu{\left(CN\right)}_2^{-}$
• C. Copper (II) oxide is red power
• D. The water of crystallization of copper sulphate is five

Answer 1

The correct option is C Copper (II) oxide is red power

(A)Copper (I) dispropotionates to copper and copper (II) ion in aqueous solution. $C{u}_{2}O+H_{2}S{O}_4\to CuS{O}_4+H_{2}O+Cu$. Hence, the statement A is true.
(B)Copper (I) can be stabilized by the formation of insoluble complex compounds such as $Cu{Cl}_2^{-}andCu{\left(CN\right)}_2^{-}$
$CuCl+C{l}^{-}\to Cu{Cl}_2^{-}$
$2Cu+2H^{+}+4C{N}^{-}\to 2Cu{\left(CN\right)}_2^{-}+H_2$. Hence, statement B is true
Hence, the statement B is true.
(C) Copper (I) oxide is red power whereas Copper (II) oxide is black solid. Hence, the statement C is not true.
(D) The water of crystallization of copper sulphate is five $\left(CuS{O}_4.5H_{2}O\right)$. Hence, the statement D is true.