Page 121 - The Periodic Table Book

Ac
–Lr

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

Actinides

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.

Atomic structure Physical properties Chemical properties Compounds
All the elements in Natural actinides are dense The actinides are reactive Actinides form colourful
this group have two metals with high melting metals and are never found compounds with halogens.
electrons in their outer points. The physical properties in pure form in nature. They Most actinide ores also
shell. Their atoms all have of most of the artificial react easily with air, the contain compounds of
seven electron shells. ones are unknown. halogens, and sulfur (S). oxygen (O) called oxides.

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