Which of the following statements is incorrect?

In both  $\left[Ni{\left(CO\right)}_4\right]$  and  ${\left[Ni{\left(CN\right)}_4\right]}^{2-}$ , the central  metal atom/ion is in the same hybridised state

There are 5 atoms lying in same plane in anionic part of ‘Z’ 
 $CuS{O}_4+KCN\left(excess\right)\to Z\left(containsCu\right)+sideproducts$

$B_2$  molecule will be diamagnetic when 2s – 2p mixing is operative and Hund’s rule  is violated

Both ZnO and $V_2{O}_5$  are amphoteric in nature