Page 122 - The Periodic Table Book

89
Ac Actinium

State: Solid
89 89 138 Discovery: 1899

Actinides Autunite This radioactive Uranite uses radioactive
This device
mineral glows brightly
in ultraviolet light.
actinium to
measure the
amount
of water.

This ore contains
uranium, which breaks
down into actinium.
Neutron probe

Rare in nature, actinium is a metal formed by
the decay of other radioactive elements. Its
atoms are unstable and break down to make the
elements francium and radon. Actinium is found
in tiny amounts in uranium ores, such as uranite,
and has limited applications. Its isotopes are
used in radiation therapy to treat cancer.

90
Th Thorium

State: Solid
Monazite 90 90 142 Discovery: 1829

The most common natural radioactive metal,
thorium is used inside vacuum tubes to allow
an electric current to flow. It can also undergo
nuclear fission, a process in which atoms split in
two and release energy. Scientists are exploring
ways of making thorium-powered nuclear
reactors that produce electricity.

This durable rock This thorium coating creates an
made of solidified lava electric current by releasing electrons.
contains 12% thorium.

This ore contains small
Thorianite crystals of thorium compounds.

120 Vacuum tube
120

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