Periodic table group

From Free net encyclopedia

A periodic table group is a vertical column in the periodic table of the chemical elements. There are 18 groups in the standard periodic table.

It is no accident that several of these correspond directly to chemical series: the periodic table was originally created to organize the known chemical series into a single coherent scheme.

The modern explanation of the pattern of the periodic table is that the elements in a group have similar (conch) configurations of the outermost electron shells of their atoms: as most chemical properties are dominated by outer electron interactions, this tends to give elements in the same group similar physical and chemical properties.

Group numbers

There are three ways of numbering the groups of the periodic table, one using Hindu-Arabic numerals and the other two using Roman numerals. The Roman numeral names are the original traditional names of the groups; the Arabic numeral names are those recommended by the International Union of Pure and Applied Chemistry (IUPAC) to replace the old names in an attempt to reduce the confusion generated by the two older, but mutually confusing, schemes.

There is considerable confusion surrounding the two old systems in use (old IUPAC and CAS) that combined the use of Roman numerals with letters. In the old IUPAC system the letters A and B were designated to the left (A) and right (B) part of the table, while in the CAS system the letters A and B were designated to main group elements (A) and transition elements (B). The former system was frequently used in Europe while the latter was most common in America. The new IUPAC scheme was developed to replace both systems as they confusingly used the same names to mean different things.


The periodic table groups are as follows (in the brackets are shown the old systems: European and American):


Note: Wikipedia style should be to replace the old names of the groups with the new IUPAC names throughout, with a historical mention of the old name where appropriate.

Periodic tables

Standard table | Vertical table | Table with names | Names and atomic masses (large) | Names and atomic masses (small) | Names and atomic masses (text only) | Inline F-block | Elements to 218 | Electron configurations | Metals and nonmetals | Table by blocks

Lists of elements

Name | Atomic symbol | Atomic number | Boiling point | Melting point | Density | Atomic mass

Groups:   1 -  2 -  3 -  4 -  5 -  6 -  7 -  8 -  9 - 10 - 11 - 12 - 13 - 14 - 15 - 16 - 17 - 18
Periods:  1  -  2  -  3  -  4  -  5  -  6  -  7  -  8  -  9
Series:   Alkalis  -  Alkaline earths  -  Lanthanides  -  Actinides  -  Transition metals  -  Poor metals  -  Metalloids  -  Nonmetals  -  Halogens  -  Noble gases
Blocks:  s-block  -  p-block  -  d-block  -  f-block  -  g-block
af:Periodieke tabel groep

ar:مجموعة جدول دوري bg:Група на периодичната система ca:Grup de la taula periòdica de:Gruppe des Periodensystems es:Grupo de la tabla periódica eo:Grupo de la perioda tabelo fr:Groupe du tableau périodique ko:주기율표 족 is:Flokkur (lotukerfið) it:Gruppo della tavola periodica mi:Rōpū ripanga pūmotu nl:Chemische groep ja:元素の族 nn:Gruppene i periodesystemet pt:Grupo (Química) ro:Grupele tabelului periodic sl:Skupina periodnega sistema su:Golongan tabel periodik fi:Ryhmä (jaksollinen järjestelmä) sv:Periodiska systemets grupper th:หมู่ในตารางธาตุ zh:族 (化学)