Science Buddies: "Ask an Expert"

I need to know the elemental make-up of sodium and chlorine please.

Sodium and chlorine are elements, they are not made up of any other elements. Sodium is made up of sodium atoms, and chlorine is made up of chlorine atoms. Can you provide more information so that we can help you understand these concepts? If I recall you also asked a question about halite. Did you understand the material in the link that I provided? The more information you can give us, the better we can help you.