In which of the following arrangements, the order is NOT according to the property indicated against it?

Options

A. `CO_2 lt SiO_2 lt SnO_2 lt PbO_2` : Increasing oxidizing power
B. `HF lt HCl lt HBr lt HI` : Increasing acidic strength
C. `NH_3 lt PH_3 lt AsH_3 lt SbH_3` : Increasing basic strength
D. `B lt C lt O lt N` : Increasing first ionization enthalpy

Answer

C

Explanation

Increasing order of basic strength: `SbH_3 lt AsH_3 lt PH_3 lt NH_3`. As the size of central atom increases, the electron density on central metal atom decreases and consequently its tendency to donate a pair of electrons decreases. Hence, the basic strength decreases as we move from `NH_3` to `BiH_3`