Identify the statement which is not correct regarding copper sulphate.

The metal that does not give the borax bead test is

Assertion : Solution of $Na_2CrO_4$ in water is intensely coloured.
Reason : Oxidation state of $Cr$ in $Na_2CrO_4$ is $+VI$.

Which of the following exhibits the maximum oxidation state of vanadium?

How is sodium chromate converted into sodium dichromate in the manufacture of potassium dichromate from chromite ore?

When a chromite ore $(A)$ is fused with sodium carbonate in free excess of air and the product is dissolved in water,a yellow solution of compound $(B)$ is obtained. After treatment of this yellow solution with sulphuric acid,compound $(C)$ can be crystallised from the solution. When compound $(C)$ is treated with $KCl$,orange crystals of compound $(D)$ crystallise out. Identify $A$ to $D$ and also explain the reactions.