When copper (ll) chloride solution is treated with excess aqueous ammonia, a deep blue solution results This is due to the presence of

  • A (CuNH4)3+ ions
  • B (CuCI4)2-ions
  • C [Cu(OH)4]2- ions
  • D Cu(H2-O)42+ IONS
  • E [cU(NH3)4] ions
waec 1988chemistry

The correct answer is E. [cU(NH3)4] ions

This is because when copper (II) chloride solution is treated with excess aqueous ammonia, a complex ion called tetraamminecopper (II) is formed.

This complex ion has a deep blue colour and consists of a central copper (II) ion surrounded by four ammonia molecules as ligands.

The equation for this reaction is:

\(CuCl_2 (aq) + 4NH_3 (aq) \rightarrow [Cu(NH_3)_4]^{2+} (aq) + 2Cl^- (aq)\)

 

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