Alternative periodic tables are tabulations of chemical elements differing significantly in their organization from the traditional depiction of the periodic system. Several have been devised, often purely for didactic reasons, as not all correlations between the chemical elements are effectively captured by the standard periodic table.
Alternative periodic tables are developed often to highlight or emphasize different chemical or physical properties of the elements which are not as apparent in traditional periodic tables. Some tables aim to emphasize both the nucleon and electronic structure of atoms. This can be done by changing the spatial relationship or representation each element has with respect to another element in the table. Other tables aim to emphasize the chemical element isolations by humans over time.
Charles Janet's left-step periodic table (1928) is the most significant alternative to the traditional depiction of the periodic system. It organizes elements according to orbital filling (instead of valence) and is widely used by physicists.
Compared to the common layout, the left-step table has these changes:
A modern version of the periodic table named the ADOMAH periodic table (2006) was constructed by Valery Tsimmerman. Its structure is based on the four quantum numbers of the electron configuration, hence it has a four-dimensional base.
In Theodor Benfey's periodic table (1964), the elements form a two-dimensional spiral, starting from hydrogen, and folding their way around two peninsulas, the transition metals, and lanthanides and actinides. A superactinide island is already slotted in. The Chemical Galaxy (2004) is organized in a similar way.
Timothy Stowe's physicist's periodic table is three-dimensional with the three axes representing the principal quantum number, orbital quantum number, and orbital magnetic quantum number. Helium is again a group 2 element.
Paul Giguère's 3-D periodic table consists of four connected billboards with the elements written on the front and the back. The first billboard has the group 1 elements on the front and the group 2 elements at the back, with hydrogen and helium omitted altogether. At a 90° angle the second billboard contains the groups 13 to 18 front and back. Two more billboards each making 90° angles contain the other elements.
Ronald L. Rich has proposed a periodic table where elements appear more than once when appropriate. He notes that hydrogen shares properties with group 1 elements based on valency, with group 17 elements because hydrogen is a non-metal but also with the carbon group based on similarities in chemical bonding to transition metals and a similar electronegativity. In this rendition of the periodic table carbon and silicon also appear in the same group as titanium and zirconium.
A chemists' table ("Newlands Revisited") with an alternative positioning of hydrogen, helium and the lanthanides was published by EG Marks and JA Marks in 2010.
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 USA 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.
In the research field of superatoms, clusters of atoms have properties of single atoms of another element. It is suggested to extend the periodic table with a second layer to be occupied with these cluster compounds. The latest addition to this multi-story table is the aluminium cluster ion Al−
7, which behaves like a multivalent germanium atom.
creation of the first man, Adam, from the dust of the earth, in Hebrew, Adomah
The periodic table is an arrangement of the chemical elements, which are organized on the basis of their atomic numbers, electron configurations and recurring chemical properties. Elements are presented in order of increasing atomic number. The standard form of the table consists of a grid with rows called periods and columns called groups.
The history of the periodic table reflects over two centuries of growth in the understanding of chemical properties, with major contributions made by Antoine-Laurent de Lavoisier, Johann Wolfgang Döbereiner, John Newlands, Julius Lothar Meyer, Dmitri Mendeleev, and Glenn T. Seaborg.Otto Theodor Benfey
Otto Theodor Benfey (born 31 October 1925) is a chemist and historian of science. Sent to England to escape Nazi Germany at age 10, he completed his education as a chemist at University College London before moving to the United States. A Quaker and a pacifist, Benfey taught at Haverford College, Earlham College, and Guilford College, retiring in 1988 as the Dana Professor of Chemistry and History of Science, Emeritus.
Benfey is known for his work on chemical education and the history of science. He edited the ACS-sponsored high school magazine Chemistry for fifteen years. His translations include The Japanese and Western Science by Masao Watanabe, The History of the International Chemical Industry by Fred Aftalion, and My 132 Semesters of Chemistry Studies by Vladimir Prelog. His books include From vital force to structural formulas (1964), Introduction to Organic Reaction Mechanisms (1970), and Robert Burns Woodward. Architect and Artist in the World of Molecules (2001).
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