When an element can exist in more than one structural form in the physical state, it is:

Glass obtained by heating a mixture of sand, lime stone and sodium carbonate is:

The mineral present in the clay is:

Materials that can return to their old shape after stretching are called:

Mendeleev ' s periodic table was based on

The formula of ammonia is:

Multiple covalent bond exist in

Group VII elements are called

In galvanization, the metal coated on iron is: