Mendeleev ' s periodic table was based on

In Moh's scale of hardness, diamond is given the value:

The structure of methane is :

The formula of ammonia is:

Duralumin consists of aluminium and:

The mineral present in the clay is:

Solder consists of:

The shape of ammonia molecule is:

An allotrope of carbon which has a spherical molecule made of 60 carbon atoms covalently bonded together is called:

Multiple covalent bond exist in