page_title: Alternative periodic tables
section_title: Variants of the classical layout
hierarchical_section_title: Alternative periodic tables / Variants of the classical layout
caption_attribution_description: Русский: Таблица Менделеева по изданию 1871 года с прочерками у предсказанных, но ещё не открытых элементов. Svenska: Dmitrij Mendelejevs periodiska system från 1871 med luckor (—) för ytterligare ämnen
context_page_description: Alternative periodic tables are tabulations of chemical elements differing in their organization from the traditional depiction of the periodic system.
  Over a thousand have been devised, often for didactic reasons, as not all correlations between the chemical elements are effectively captured by the standard periodic table.
context_section_description: From Mendeleev's original periodic table, elements have been basically arranged by valence (groups in columns) and the repetition therein (periods in rows). Over the years and with discoveries in atomic structure, this schema has been adjusted and expanded, but not changed as a principle.
  The oldest periodic table is the short form table (columns I–VIII) by Dmitri Mendeleev, which shows secondary chemical kinships. For example, the alkali metals and the coinage metals (copper, silver, gold) are in the same column because both groups tend to have a valence of one. This format is still used by many, as shown by this contemporary Russian short form table, which includes all elements and element names until roentgenium.
  H. G. Deming used the so-called long periodic table (18 columns) in his textbook "General Chemistry", which appeared in the US for the first time in 1923 (Wiley), and was the first to designate the first two and the last five main groups with the notation "A", and the intervening transition groups with the notation "B".
  The numeration was chosen so that the characteristic oxides of the B groups would correspond to those of the A groups. The iron, cobalt, and nickel groups were designated neither A nor B. The noble-gas group was originally attached (by Deming) to the left side of the periodic table. The group was later switched to the right side and usually labeled as group VIIIA.
caption: Mendeleev's 1871 periodic table in VIII columns. Nowadays, roughly spoken, pairs of Reihen are shown as grouplabels A, B (for example: Reihen 4, 5 are written as period 3 and groups (columns) IA–VIIIA, IB–VIIIB).
exif: {}