Which of the following is a neutral complex?

Explain the classification of ligands on the basis of their denticity.

$A$ $2 \ L$ solution is prepared by mixing $0.02 \ mol$ of $[Co(NH_3)_5SO_4]Br$ and $0.02 \ mol$ of $[Co(NH_3)_5Br]SO_4$. If $1 \ L$ of this mixture $X$ is treated with $AgNO_3$ to give $Y$,and another $1 \ L$ of mixture $X$ is treated with $BaCl_2$ to give $Z$,find the moles of $Y$ and $Z$.

Assertion : When $NO$ reacts with $FeSO_4$,a brown coloured complex is formed.
Reason : In the complex,the coordination number of $Fe$ is $6$.

Which of the following statements is true about $[Cu(NH_3)_4]SO_4$?

Explain the terms: Coordination Number,Coordination Sphere,and Coordination Polyhedron.