In which one of the pairs of ion given, there is an ion that forms a co-ordination compound with both aqueous sodium hydroxide and ammonia and an other ion that forms a co-ordination compound only with aqueous sodium hydroxide?

Options

A. `Pb^(+2) , Cu^(+2)`
B. `Zn^(+2), Al^(+3)`
C. `Cu^(+2),Zn^(+2)`
D. `Al^(+3),Cu^(+2)`

Answer

B

Explanation

`Zn^(+2)` forms coordination compound with NaOH to give `Na_2[Zn(OH)_4]` and with ammonia it gives `[Zn(NH_3)_4]^(+2)` while Aluminium only forms complex with NaOH to give Na `[Al(OH)_4]`