A Visual Encyclopedia of the Periodic Table

Actinides

Atomic structure

All the elements in

this group have two

electrons in their outer

shell. Their atoms all have

seven electron shells.

Physical properties

Natural actinides are dense

metals with high melting

points. The physical properties

of most of the artificial

ones are unknown.

Chemical properties

The actinides are reactive

metals and are never found

in pure form in nature. They

react easily with air, the

halogens, and sulfur (S).

Compounds

Actinides form colourful

compounds with halogens.

Most actinide ores also

contain compounds of

oxygen (O) called oxides.

Ac Th Pa U Np Pu Am Cm Bk Cf Es Fm Md No Lr

These metals are named after actinium (Ac), the first member of the

group. Although this group is often shown as the bottom row in the

periodic table, to save space, they actually sit between radium (Ra),

an alkali earth metal, and Rutherfodium (Rf), a transition metal. All

the elements in this group are radioactive, and the final nine members

are artificially produced in laboratories.

Ac

–Lr

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