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

Chrome yellow is chemically known as

Preparation of potassium permanganate from $MnO_2$ involves a two-step process in which the $1^{st}$ step is a reaction with $KOH$ and $KNO_3$ to produce:

The oxidising ability of the given anions follows the order:

$CoO \cdot Al_2O_3$ is called

Which of the following compounds is amphoteric?