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Properties of Matter Element Card, Lesson 21



Melting point

1132° C

Boiling point

3818° C


19.1 g/cm³



Other physical properties

Uranium is radioactive and malleable, but it is not a very good conductor of electricity.

Chemical properties

Uranium gets a thin coat of oxide when left in the air, and it reacts with water. Uranium powder or chips react violently with air.


Uranium compounds come in a variety of colors (uranium dioxide, dark brown; uranium trioxide, orange; uranium fluoride, white).


Uranium is used in nuclear weapons and nuclear reactors.


Uranium is highly radioactive, and even small amounts can be a health hazard.

Hands holding a large button of Uranium

Uranium is used inside nuclear reactors and nuclear weapons.


Historic photo of the atomic cloud over Hiroshima

A nuclear bomb containing uranium was dropped by the United States on Hiroshima, Japan, toward the end of World War II. Because of their terrifying destructiveness, only two nuclear bombs have ever been used in war. The other, dropped on the Japanese city of Nagasaki, contained a different radioactive material, called plutonium.

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