4th Period: Potassium and Calcium—Electrons go into the fourth energy level. A small piece of sodium metal is placed in water. The sodium reacts with the water and gets very hot, producing sodium ...

Sodium metabisulphite is also used in water treatment as an anti-chlor agent to remove chlorine and heavy metals from water ...

A small piece of sodium metal is placed in a flask of chlorine gas. A little water helps expose the sodium so it can react with the chlorine gas. The reaction releases a lot of heat as the ionic ...