What are the charges of the groups of elements on the periodic table?
+1 for alkali metals, +2 for for alkaline earth, +3 for boron family, +/-4 for carbon family, -3 for nitrogen family, -2 for oxygen family, -1 for halogens
Metals tend to lose electrons to become stable. The representative elements (in the s and p blocks) will lose their valence electrons to become more stable. Transition metals often can lose varying numbers of electrons depending on the situation, so they can have many different possible oxidation states.
Nonmetallic elements will tend to gain electrons to become more stable. They will normally add enough electrons to fill their outer energy level with a total of 8 electrons.
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