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Families of Element - The Search For Patterns Among The Elements, The Main-group Families, The Transition Metals - Hydrogen: The elemental orphan, Other families of elements

Science EncyclopediaScience & Philosophy: Electrophoresis (cataphoresis) to Ephemeral

A family of chemical elements usually consists of elements that are in the same group (the same column) on the periodic table. The term is also applied to certain closely related elements within the same period (row). Just as the individual members in a human family are all different but have common characteristics, like hair color, so to do the elements in a chemical family have certain properties in common, and others that make them unique.

Hydrogen: The elemental orphan

When the elements are organized into families, hydrogen presents a problem. In some of its properties, hydrogen resembles the alkali metals, but it also shows some similarities to the halogens. Many periodic tables include hydrogen in group 1; others show it in groups 1 and 17. An alternative approach is to recognize hydrogen as being unique and not to assign it to a family.

Other families of elements

In addition to the main-group families, other families of elements can be identified among the remaining elements of the periodic table.

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