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Properties of Matter Element Card 4, Lesson 21



Melting point

3550° C

Boiling point

4827° C


1.9 g/cm³ (charcoal); 2.3 g/cm³ (graphite, or carbon rod); 3.5 g/cm³ (diamond).



Other physical properties

There are three forms of carbon: charcoal, graphite, and diamond (which is the hardest substance known). Each form has different physical properties.

Chemical properties

Carbon combines with oxygen in the air to form carbon dioxide.


Carbon forms a wide variety of compounds, many of which are important components in living things. It is present in the compounds found in coal and limestone.


Charcoal is used in filters to absorb impurities in water or smells from the air. It is also used as a fuel for cooking (for example, in barbeques). Graphite is used as a lubricant and to make pencil leads. Diamond is used in jewelry and in cutting tools (because of its hardness).


Carbon is the sixth most abundant element in the universe. Combined with other elements, carbon is found in all substances made from oil, including plastics.

The Oppenheimer diamond, a large uncut diamond

This diamond is uncut.


The Hope Diamond, a famous large blue diamond, set into a necklace

These diamonds have been cut to make a piece of jewelry.

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