This article may require cleanup to meet Wikipedia's quality standards. Please improve this article if you can. (September 2006)

This article needs additional citations for verification. Please help improve this article by adding reliable references. Unsourced material may be challenged and removed. (April 2007)

The periodic table is a tabular method of displaying the chemical elements. Although earlier precursors exist, its invention is generally credited to the Russian chemist Dmitri Mendeleev in 1869.^[1] The table is a visual representation of the periodic law which states that certain properties of elements repeat periodically when arranged by atomic number. The table arranges elements into vertical columns (Groups) and horizontal rows (Periods) to display these commonalities. Image File history File links Question_book-3. ... The Periodic Table redirects here. ... Portrait of Dmitri Mendeleev by Ilya Repin (Russian: , Dmitri Ivanovich Mendeleev  ) (8 February [O.S. 27 January] 1834 in Tobolsk – 2 February [O.S. 20 January] 1907 in Saint Petersburg), was a Russian chemist and inventor. ... The periodic table of the chemical elements A chemical element, or element, is a type of atom that is distinguished by its atomic number; that is, by the number of protons in its nucleus. ... See also: List of elements by atomic number In chemistry and physics, the atomic number (also known as the proton number) is the number of protons found in the nucleus of an atom. ...

In the beginning

People have known about basic chemical elements such as gold, silver, and copper from antiquity, as these can all be discovered in nature in native form and are relatively simple to mine with primitive tools.^[2] Aristotle, a philosopher, theorised that everything is made up of a mixture of one or more of four elements. They were earth, water, air, and fire. This was more like the four states of matter (in the same order): solid, liquid, gas, and plasma, though he also theorised that they change into new substances to form what we see. The periodic table of the chemical elements A chemical element, or element, is a type of atom that is distinguished by its atomic number; that is, by the number of protons in its nucleus. ... GOLD refers to one of the following: GOLD (IEEE) is an IEEE program designed to garner more student members at the university level (Graduates of the Last Decade). ... This article is about the chemical element. ... For other uses, see Copper (disambiguation). ... For other uses, see Aristotle (disambiguation). ... Many ancient philosophies used a set of archetypal classical elements to explain patterns in nature. ... . Bön . Hinduism (Tattva) and Buddhism (MahābhÅ«ta) Prithvi / Bhumi — Earth Ap / Jala — Water Vayu / Pavan — Air / Wind Agni / Tejas — Fire Akasha — Aether . ... Chinese Wood (木) | Fire (火) Earth (土) | Metal (金) | Water (æ°´) Japanese Earth (地) | Water (æ°´) | Fire (火) | Air / Wind (風) | Void / Sky / Heaven (空) Hinduism and Buddhism Vayu / Pavan — Air / Wind Agni / Tejas — Fire Akasha — Aether Prithvi / Bhumi — Earth Ap / Jala — Water Water has been important to all peoples of the earth, and it is rich in spiritual tradition. ... . Bön . Hinduism (Tattva) and Buddhism (MahābhÅ«ta) Prithvi / Bhumi — Earth Ap / Jala — Water Vayu / Pavan — Air / Wind Agni / Tejas — Fire Akasha — Aether . ... . Bön . Hinduism (Tattva) and Buddhism (MahābhÅ«ta) Prithvi / Bhumi — Earth Ap / Jala — Water Vayu / Pavan — Air / Wind Agni / Tejas — Fire Akasha — Aether . ... In the physical sciences, a phase is a set of states of a macroscopic physical system that have relatively uniform chemical composition and physical properties (i. ... This box:      For other uses, see Solid (disambiguation). ... For other uses, see Liquid (disambiguation). ... For other uses, see Gas (disambiguation). ... For other uses, see Plasma. ...

Hennig Brand was the first person recorded to have discovered a new element. Brand was a bankrupt German merchant who was trying to discover the Philosopher's Stone — a mythical object that was supposed to turn inexpensive base metals into gold. He experimented with distilling human urine until in 1649^[3] he finally obtained a glowing white substance which he named phosphorus. He kept his discovery secret, until 1680 when Robert Boyle rediscovered it and it became public. The Alchemist in Search of the Philosophers Stone (1771) by Joseph Wright depicting Hennig Brand discovering phosphorus (the glow shown is exaggerated) Hennig Brand(t) (c. ... For other uses, see Philosophers stone (disambiguation). ... This article is about metallic materials. ... // Events January 30 - King Charles I of England, Scotland and Ireland is beheaded. ... General Name, symbol, number phosphorus, P, 15 Chemical series nonmetals Group, period, block 15, 3, p Appearance waxy white/ red/ black/ colorless Standard atomic weight 30. ... Events First Portuguese governor was appointed to Macau The Swedish city Karlskrona was founded as the Royal Swedish Navy relocated there. ... For the American art director and production designer, see Robert F. Boyle Robert Boyle (25 January 1627 – 30 December 1691) was a natural philosopher, chemist, physicist, inventor, and early gentleman scientist, noted for his work in physics and chemistry. ...

By 1869^[3], a total of 63^[3] elements had been discovered. As the number of known elements grew, scientists began to recognize patterns in the way chemicals reacted and began to devise ways to classify the elements. Year 1869 (MDCCCLXIX) is a common year starting on Friday (link will display the full calendar) of the Gregorian calendar (or a common year starting on Wednesday of the 12-day slower Julian calendar). ...

Antoine Laurent de Lavoisier

Wikipedia does not have an article with this exact name. ... Wikipedia does not have an article with this exact name. ...

Antoine-Laurent de Lavoisier

Lavoisier's Traité Élémentaire de Chimie (Elementary Treatise of Chemistry, 1789, translated into English by Robert Kerr) is considered to be the first modern chemical textbook. It contained a list of elements, or substances that could not be broken down further, which included oxygen, nitrogen, hydrogen, phosphorus, mercury, zinc, and sulfur. It also forms the basis for the modern list of elements. His list, however, also included light and caloric, which he believed to be material substances. While many leading chemists of the time refused to believe Lavoisier's new revelations, the Elementary Treatise was written well enough to convince the younger generation. Lavoisier redirects here. ... Year 1789 (MDCCLXXXIX) was a common year starting on Thursday (link will display the full calendar) of the Gregorian calendar (or a common year starting on Monday of the 11-day slower Julian calendar). ... Robert Kerr (1755 - October 11, 1813) was a scientific writer and translator from Scotland. ... Three textbooks. ... This article is about the chemical element and its most stable form, or dioxygen. ... General Name, symbol, number nitrogen, N, 7 Chemical series nonmetals Group, period, block 15, 2, p Appearance colorless gas Standard atomic weight 14. ... This article is about the chemistry of hydrogen. ... General Name, symbol, number phosphorus, P, 15 Chemical series nonmetals Group, period, block 15, 3, p Appearance waxy white/ red/ black/ colorless Standard atomic weight 30. ... This article is about the element. ... General Name, symbol, number zinc, Zn, 30 Chemical series transition metals Group, period, block 12, 4, d Appearance bluish pale gray Standard atomic weight 65. ... This article is about the chemical element. ... For other uses, see Light (disambiguation). ... Caloric redirects here. ...

This model only classified elements into metals and non-metals and thus was not accepted.

Alexandre-Emile Béguyer de Chancourtois

Alexandre-Emile Béguyer de Chancourtois, a French geologist, was the first person to notice the periodicity of the elements — similar elements seem to occur at regular intervals when they are ordered by their atomic weights. He devised an early form of periodic table, which he called the telluric helix. With the elements arranged in a spiral on a cylinder by order of increasing atomic weight, de Chancourtois saw that elements with similar properties lined up vertically. His chart included some ions and compounds in addition to elements. His paper was published in 1862, but used geological rather than chemical terms and did not include a diagram; as a result, it received little attention until the work of Dmitri Mendeleev.^[4] Alexandre-Emile Béguyer de Chancourtois Alexandre-Emile Béguyer de Chancourtois (January 20, 1820 - November 14, 1886) was a French geologist and mineralogist who was the first to arrange the chemical elements in order of atomic weights, doing so in 1862. ... This article is about 1862 . ... Portrait of Dmitri Mendeleev by Ilya Repin (Russian: , Dmitri Ivanovich Mendeleev  ) (8 February [O.S. 27 January] 1834 in Tobolsk – 2 February [O.S. 20 January] 1907 in Saint Petersburg), was a Russian chemist and inventor. ...

John Newlands

John Newlands was an English chemist who in 1865 classified^[5] the 56 elements that had been discovered at the time into 11 groups which were based on similar physical properties. Born 26th November 1837, Newlands created the Law of Octaves in 1866. ... Year 1865 (MDCCLXV) was a common year starting on Sunday (link will display the full calendar) of the Gregorian calendar (or a common year starting on Friday of the 12-day slower Julian calendar). ...

Newlands noted that many pairs of similar elements existed which differed by some multiple of eight in atomic weight. However, his law of octaves, likening this periodicity of eights to the musical scale, was ridiculed by his contemporaries. It was not until the following century, with Gilbert N. Lewis' valence bond theory (1916) and Irving Langmuir's octet theory of chemical bonding^[6][7] (1919) that the importance of the periodicity of eight would be accepted. Lewis in the Berkeley Lab Gilbert Newton Lewis (October 23, 1875-March 23, 1946) was a famous American physical chemist. ... In chemistry, valence bond theory explains the nature of a chemical bond in a molecule in terms of atomic valencies. ... Year 1916 (MCMXVI) was a leap year starting on Saturday (link will display the full calendar) of the Gregorian calendar (or a leap year starting on Friday of the 13-day-slower Julian calendar). ... Irving Langmuir (January 31, 1881 in Brooklyn, New York - August 16, 1957 in Woods Hole, Massachusetts) was an American chemist and physicist. ... Year 1919 (MCMXIX) was a common year starting on Wednesday (link will display the full calendar). ...

The first periodic table

Dmitri Ivanovich Mendeleyev

Dmitri Mendeleev, also spelt Dmitry Mendeleyev, middle name (patronymic) Ivanovich, a Siberian-born Russian chemist, was the first scientist to make a periodic table much like the one we use today. Mendeleev arranged the elements in a table ordered by atomic mass. It is sometimes said that he played "chemical solitaire" on long train rides using cards with various facts of known elements.^[8] On March 6, 1869, a formal presentation was made to the Russian Chemical Society, entitled The Dependence Between the Properties of the Atomic Weights of the Elements. His table was published in an obscure Russian journal but quickly republished in a German journal, Zeitschrift für Chemie (Eng., "Chemistry Magazine"), in 1869. It stated: Image File history File links Дмитрий_Иванович_Менделеев_4. ... Image File history File links Дмитрий_Иванович_Менделеев_4. ... Portrait of Dmitri Mendeleev by Ilya Repin (Russian: , Dmitri Ivanovich Mendeleev  ) (8 February [O.S. 27 January] 1834 in Tobolsk – 2 February [O.S. 20 January] 1907 in Saint Petersburg), was a Russian chemist and inventor. ... Look up patronymic in Wiktionary, the free dictionary. ... This article is about Siberia as a whole. ... The Periodic Table redirects here. ... Stylized lithium-7 atom: 3 protons, 4 neutrons & 3 electrons (~1800 times smaller than protons/neutrons). ... is the 65th day of the year (66th in leap years) in the Gregorian calendar. ... Year 1869 (MDCCCLXIX) is a common year starting on Friday (link will display the full calendar) of the Gregorian calendar (or a common year starting on Wednesday of the 12-day slower Julian calendar). ...

1. The elements, if arranged according to their atomic weights, exhibit an apparent periodicity of properties.
2. Elements which are similar as regards to their chemical properties have atomic weights which are either of nearly the same value (e.g., Pt, Ir, Os) or which increase regularly (e.g., K, Rb, Cs).
3. The arrangement of the elements, or of groups of elements in the order of their atomic weights, corresponds to their so-called valencies, as well as, to some extent, to their distinctive chemical properties; as is apparent among other series in that of Li, Be, Ba, C, N, O, and Sn.
4. The elements which are the most widely diffused have small atomic weights.
5. The magnitude of the atomic weight determines the character of the element, just as the magnitude of the molecule determines the character of a compound body.
6. We must expect the discovery of many yet unknown elements–for example, elements analogous to aluminium and silicon–whose atomic weight would be between 65 and 75.
7. The atomic weight of an element may sometimes be amended by a knowledge of those of its contiguous elements. Thus the atomic weight of tellurium must lie between 123 and 126, and cannot be 128.
8. Certain characteristic properties of elements can be foretold from their atomic weights.

Advantages The periodic table of the chemical elements A chemical element, or element, is a type of atom that is distinguished by its atomic number; that is, by the number of protons in its nucleus. ... ... Aluminum redirects here. ... Not to be confused with Silicone. ... General Name, Symbol, Number tellurium, Te, 52 Chemical series metalloids Group, Period, Block 16, 5, p Appearance silvery lustrous gray Standard atomic weight 127. ...

• Mendeleev predicted the discovery of other elements and left space for these new elements, namely eka-silicon (germanium), eka-aluminium (gallium), and eka-boron (scandium). Thus, there was no disturbance in the periodic table.
• He pointed out that some of the then current atomic weights were incorrect.
• He provided for variance from atomic weight order

Disadvantages General Name, Symbol, Number germanium, Ge, 32 Chemical series metalloids Group, Period, Block 14, 4, p Appearance grayish white Standard atomic weight 72. ... Not to be confused with Galium. ... General Name, symbol, number scandium, Sc, 21 Chemical series transition metals Group, period, block 3, 4, d Appearance silvery white Standard atomic weight 44. ...

• There was no place for the isotopes of the various elements.
• His table did not include any of the noble gases, which hadn't been discovered. But these were added by Sir William Ramsay as Group 0, without any disturbance to the basic concept of the periodic table.

This version of Mendeleev's periodic table, from 1891 is lacking the noble gases

Unknown to Mendeleev, Lothar Meyer was also working on a periodic table. In his work published in 1864, Meyer presented only 28 elements, classified not by atomic weight but by valence alone. Also, Meyer never came to the idea of predicting new elements and correcting atomic weights. Only a few months after Mendeleev published his periodic table of all known elements (and predicted several new elements to complete the table, plus some corrected atomic weights), Meyer published a virtually identical table. Some people consider Meyer and Mendeleev the cocreators of the periodic table, although most agree that Mendeleev's accurate prediction of the qualities of the undiscovered elements lands him the larger share of credit. In any case, at the time Mendeleev's predictions greatly impressed his contemporaries and were eventually found to be correct. An English chemist, William Odling, also drew up a table that is remarkably similar to that of Mendeleev in 1864. This article is about the chemical series. ... For other uses, see William Ramsay (disambiguation). ... Image File history File links Download high resolution version (2116x2556, 864 KB) File links The following pages link to this file: Dmitri Mendeleev ... Image File history File links Download high resolution version (2116x2556, 864 KB) File links The following pages link to this file: Dmitri Mendeleev ... Mendeleyevs portrait by Ilya Repin. ... This article is about the chemical series. ... Julius Lothar Meyer (19 August 1830 - 11 April 1895) was born in Varel, at that time belonging to the duchy of Oldenburg, now part of Germany. ... 1864 (MDCCCLXIV) was a leap year starting on Friday (see link for calendar) of the Gregorian calendar or a leap year starting on Sunday of the 12-day-slower Julian calendar. ... ... For other uses, see Valence. ... William Odling (1829 - 1921) was an English chemist who contributed to the development of the periodic table. ...

Henry Moseley

In 1914 Henry Moseley found a relationship between an element's X-ray wavelength and its atomic number and therefore resequenced the table by electronic charge rather than atomic weight. Before this discovery, atomic numbers were just sequential numbers based on an element's atomic weight. Moseley's discovery showed that atomic numbers had an experimentally measurable basis. Year 1914 (MCMXIV) was a common year starting on Thursday (link will display the full calendar) of the Gregorian calendar (or a common year starting on Wednesday of the 13-day-slower Julian calendar). ... This article is about the physicist; for the naturalist see Henry Nottidge Moseley Henry Moseley at work. ... In the NATO phonetic alphabet, X-ray represents the letter X. An X-ray picture (radiograph) taken by Röntgen An X-ray is a form of electromagnetic radiation with a wavelength approximately in the range of 5 pm to 10 nanometers (corresponding to frequencies in the range 30 PHz... See also: List of elements by atomic number In chemistry and physics, the atomic number (also known as the proton number) is the number of protons found in the nucleus of an atom. ...

Moseley's research also showed that there were gaps in his table at atomic numbers 43 and 61 which are now known to be radioactive and not naturally occurring. Following in the footsteps of Dmitri Mendeleyev, Henry Moseley also predicted new elements. Radioactive decay is the set of various processes by which unstable atomic nuclei (nuclides) emit subatomic particles. ...

Glenn T. Seaborg

During his Manhattan Project research in 1943 Glenn T. Seaborg experienced unexpected difficulty isolating Americium (95) and Curium (96). He began wondering if these elements more properly belonged to a different series which would explain why the expected chemical properties of the new elements were different. In 1945, he went against the advice of colleagues and proposed a significant change to Mendelev's table: the actinoid series (previously called the actinide series). Year 1943 (MCMXLIII) was a common year starting on Friday (the link will display full 1943 calendar) of the Gregorian calendar. ... Glenn Theodore Seaborg (April 19, 1912 – February 25, 1999) won the 1951 Nobel Prize in Chemistry for discoveries in the chemistry of the transuranium elements,[1] contributed to the discovery and isolation of ten elements, developed the actinide concept and was the first to propose the actinide series which led... General Name, Symbol, Number americium, Am, 95 Chemical series actinides Group, Period, Block n/a, 7, f Appearance silvery white sometimes yellow Standard atomic weight (243) g·mol−1 Electron configuration [Rn] 5f7 7s2 Electrons per shell 2, 8, 18, 32, 25, 8, 2 Physical properties Phase solid Density (near... General Name, Symbol, Number curium, Cm, 96 Chemical series actinides Group, Period, Block ?, 7, f Appearance silvery Atomic mass (247) g/mol Electron configuration [Rn] 5f7 6d1 7s2 Electrons per shell 2, 8, 18, 32, 25, 9, 2 Physical properties Phase solid Density (near r. ... Year 1945 (MCMXLV) was a common year starting on Monday (link will display the full calendar). ... The actinide series encompasses the 14 chemical elements that lie between actinium and nobelium on the periodic table with atomic numbers 89 - 102 inclusive. ...

Seaborg's actinide concept of heavy element electronic structure, predicting that the actinides form a transition series analogous to the rare earth series of lanthanide elements, is now well accepted in the scientific community and included in all standard configurations of the periodic table. The actinide series are the second row of the f-block (5f series) and comprise the elements from Actinium to Lawrencium. Seaborg's subsequent elaborations of the actinide concept theorized a series of superheavy elements in a transactinide series comprising elements 104 through 121 and a superactinide series inclusive of elements 122 through 153. The actinide concept in nuclear chemistry was first theorized by Glenn T. Seaborg in 1944, resulting in the correction of Mendeleyevs periodic table of the elements by placing a new actinide series below the lanthanide series. ...

Curiosities

• In 1998, a 35-by-65 foot periodic table at the Science Museum of Virginia was declared the world's largest periodic table by the Guinness Book of World Records.^[9]

The Science Museum of Virginia is a science museum located in Richmond, Virginia. ... The Guinness Book of Records (or in recent editions Guinness World Records, and in previous US editions Guinness Book of World Records) is a book published annually, containing an internationally recognized collection of superlatives: both in terms of human achievement and the extrema of the natural world. ...

See also

• Prout's hypothesis
• History of chemistry
• Discoveries of the chemical elements
• Periodic table

Prouts hypothesis was an early 19th century attempt to explain the existence of the various chemical elements through a hypothesis regarding the internal structure of the atom. ... Portrait of Monsieur Lavoisier and his Wife, by Jacques-Louis David The history of chemistry is long and convoluted. ... The discovery of the elements known to exist today is presented here in chronological order. ... The Periodic Table redirects here. ...

References

1. ^ IUPAC article on periodic table
2. ^ Scerri, E. R. (2006). The Periodic Table: Its Story and Its Significance; New York City, New York; Oxford University Press.
3. ^ ^{a b c} A Brief History of the Development of Periodic Table.
4. ^ Annales des Mines history page.
5. ^ in a letter published in the Chemical News in February 1863, according to the Notable Names Data Base
6. ^ Irving Langmuir, “The Structure of Atoms and the Octet Theory of Valence”, Proceedings of the National Academy of Science, Vol. V, 252, Letters (1919) - online at [1]
7. ^ Irving Langmuir, “The Arrangement of Electrons in Atoms and Molecules”, Journal of the American Chemical Society, Vol. 41, No, 6, pg. 868 (June 1919) - beginning and ending of the paper are transcribed online at [2]; the middle is missing
8. ^ Physical Science, Holt Rinehart & Winston (January 2004), page 302 ISBN 0-03-073168-2
9. ^ Richmond in the Record Books (August 18, 2004).

External links

• WebElements periodic table
• Development of the periodic table
• Classification of the elements
• The path to the periodic table
• Web page listing several scholarly and semi-popular articles on various aspects of the periodic system and underlying theoretical concepts. Some are dowloadable!