From the stability constant (hypothetical vlues ) , given below, predict which is the most stable complex ?

Options

A. `Cu^(2)+4NH_(3) to [Cu(NH_(3))_(4)]^(2+), K=4.5xx10^(11)`
B. `Cu^(2)+4CN^(-) to [Cu(CN)_(4)]^(2-), K=2.0xx10^(27)`
C. `Cu^(2)+2en to [Cu(en)_(2)]^(2+), K=3.0xx10^(15)`
D. `Cu^(2)+4H_(2)O to [Cu(H_(2)O)_(4)]^(2+), K=9.5xx10^(8)`

Answer

B