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Properties of Matter Element Card 18, Lesson 21



Melting point

98° C

Boiling point

883° C




Sodium is usually covered in a layer of dull gray oxide; however, when scratched a shiny silver color is revealed.

Other physical properties

Sodium is soft enough to be easily cut with a knife. Sodium is a good conductor of electricity.

Chemical properties

Sodium is very reactive. It reacts quickly with the oxygen in air. It reacts very quickly with water, forming sodium hydroxide and releasing hydrogen.


Compounds of sodium are white. They are very common—sodium chloride (table salt) is probably the best known.



Sodium is the sixth most abundant element in Earth's crust.

Sodium being cut with a knife

Sodium reacts readily with oxygen and is usually covered with a layer of sodium oxide. It is stored under oil to prevent a reaction. It is so soft that it can be easily cut with a knife, revealing a shiny silver surface.


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