Group 16 The Oxygen Family

Group 16 The Oxygen Family 22-5 Group 15 The Nitrogen Family 22-6 Hydrogen A Unique Element... 

Similar to the other groups that have been presented, group 16 (VI A) (the chal-cogens or the oxygen family) starts with an element whose physical properties and chemical reactivity do not resemble those of the rest of the group. Here also, the metallic character increases down the group oxygen and sulphur are nonmetals, selenium and tellurium are considered metalloids (they are referred to as a metal when in elemental form), while radioactive polonium is classified either as a post-transitional metal or metalloid (Hawkes 2010 Bentor 2011). 

One-to-one combinations also occur when the cation has a +2 charge and the anion has a -2 charge, since such a combination would also result in a neutral or uncharged unit. Examples of this include any alkaline earth metal ion (+2) combined with a sulfate ion and carbonate ions, and also an oxide ion (0 ), or any other monatomic ion of the oxygen family (Group VIA or 16), such as the sulfide ion (S ). Thus we have compounds with such formulas as CaO, MgS04, and BaCOj and corresponding formula units. 

The halogens are the family of nonmetal elements in group 17 (VIIA) that are located just to the right of the oxygen group 16 on the periodic table of chemical elements. They are fluorine (F), chlorine (Cl), bromine (Br), iodine (I), and astatine (At). 

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