Sodium is a highly combustible element and the addition of water can make it explode. In this video we see a drop of water added to a small piece of sodium in a flask filled with chlorine gas. The distinctive yellow color of the light emitted is due to sodium’s “D lines” – this is often used in street lighting. This experiment produces a great deal of heat. When you combine sodium and chlorine, you get sodium chloride – common salt.

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