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:

The vertical columns of elements with similar properties are called

The size of the charge on an ion is a measure of its:

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

The formula of ionic compound magnesium chloride is

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

A metalloid among the following

The scientist awarded Nobel Prize for Isolation of all elements in the group zero

A pale yellow gas at room temperature which is dangerously reactive