When a small amount of vanadium is added to steel,it becomes:

The colorless species is

The oxidising ability of the given anions follows the order:

The blue borax bead is obtained by which of the following?

Which of the following is a product of the first step and is used as a reactant in the next step for the manufacture of $K_{2}Cr_{2}O_{7}$ from concentrated chromite ore?

Ferric sulphate on heating gives: