<Ul> <Li> Nutritional elements </Li> <Li> Platinum - group metals (PGM) </Li> <Li> Rare - earth elements </Li> <Li> Refractory metals </Li> <Li> Precious metals </Li> <Li> Coinage metals </Li> <Li> Noble metal </Li> <Li> Heavy metals </Li> <Li> Native metals </Li> <Li> Transuranium elements </Li> <Li> Transactinide elements </Li> <Li> Major actinides </Li> <Li> Minor actinides </Li> </Ul> <Li> Platinum - group metals (PGM) </Li> <Li> Rare - earth elements </Li> <Tr> <Th> Elements </Th> <Td> <Table> <Tr> <Th> Lists </Th> <Td> <Ul> <Li> By: Abundance (in humans) </Li> <Li> Atomic properties </Li> <Li> Nuclear stability </Li> <Li> Production </Li> <Li> Symbol </Li> </Ul> </Td> </Tr> <Tr> <Th> Properties </Th> <Td> <Ul> <Li> Atomic weight </Li> <Li> Crystal structure </Li> <Li> Electron affinity </Li> <Li> Electron configuration </Li> <Li> Electronegativity <Ul> <Li> Allen </Li> <Li> Pauling </Li> </Ul> </Li> <Li> Goldschmidt classification </Li> <Li> Maximum valence </Li> </Ul> </Td> </Tr> <Tr> <Th> Data pages </Th> <Td> <Ul> <Li> Abundance </Li> <Li> Atomic radius </Li> <Li> Boiling point </Li> <Li> Critical point </Li> <Li> Density </Li> <Li> Elasticity </Li> <Li> Electrical resistivity </Li> <Li> Electron affinity </Li> <Li> Electron configuration </Li> <Li> Electronegativity </Li> <Li> Hardness </Li> <Li> Heat capacity </Li> <Li> Heat of fusion </Li> <Li> Heat of vaporization </Li> <Li> Ionization energy </Li> <Li> Melting point </Li> <Li> Oxidation state </Li> <Li> Speed of sound </Li> <Li> Thermal conductivity </Li> <Li> Thermal expansion coefficient </Li> <Li> Vapor pressure </Li> </Ul> </Td> </Tr> </Table> </Td> </Tr>

Using the periodic chart indicate the most common charge of elements ca