Sub-race - Azok

In the short-period table up until the IUPAC 1990 Recommendation for the Nomenclature of Inorganic Compounds, Groups 1 to 10 of the current long-period table were called IA to VIIIA, and Groups 11 to 17 were called subgroups IA to VIIB (mainly in Europe, IUPAC, 1970 Recommendation), or Groups 1 to 2 were called IA and IIA, Groups 3 to 7 were called IIIB to VIIB, Groups 8 to 10 were called VIII, Groups 11 to 12 were called IB and IIB, and Groups 13 to 18 were called subgroups IIIA to VIIIA (or Group 18 was called Group 0, mainly in the United States, CAS system). In the latter method of calling them, subgroup A was the typical elements, and subgroups B and VIII were the transition elements. As such, there were two different classifications of the A and B subgroups, which was confusing, so the 1990 Recommendation recommended a long-period table for Groups 1 to 18 without using the A and B names.

Source: Morikita Publishing "Chemical Dictionary (2nd Edition)" Information about the Chemical Dictionary 2nd Edition

IUPACの無機化合物命名法1990年勧告に至るまでの短周期型周期表では，現在の長周期型周期表の1～10族をⅠA～ⅧA，11～17族をⅠA～ⅦB亜族(主としてヨーロッパ，IUPAC．1970年勧告)，あるいは1～2族をⅠA，ⅡA，3～7族をⅢB～ⅦB，8～10族をⅧ，11～12族をⅠB，ⅡB，13～18族をⅢA～ⅧA亜族(または18族を0族，主としてアメリカ，CAS方式)とよんでいた．後者のよび方では，A亜族は典型元素，B亜族とⅧ族が遷移元素となっている．このように，A，B亜族の分類に二通りあってまぎらわしいので，1990年勧告で，A，Bを用いない1～18族の長周期型周期表が勧告された．

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