Several important groups are given names. Group IA (1) metals (notincluding hydrogen) are called the alkali metals. Group IIA (2) elementsFigure 2-1 Periods and element types in the periodic tableare known as the alkaline earth metals. Group VIIA (17) elements arecalled the halogens. Group IB (11) metals are known as the coinage metals.Group 0 (18) elements are known as the noble gases. These nameslessen the need for using group numbers and thereby lessen the confusionfrom different systems
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