A piece of magnesium ribbon was heated to redness in an atmosphere of nitrogen and then cooled with water. The gas evolved is

A piece of magnesium ribbon was heated to redness in an atmosphere of nitrogen and then treated with water , the gas evoloved is:

When magnesium ribbon is heated to redness in an atmosphere of nitrogen and subsequently cooled with water, the gas evolved is-

What will happen if aluminium is heated with coke in an atmosphere of nitrogen?