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List of Oxidation States of the Elements 1 List of oxidation states of the elements 1 List of oxidation states of the elements This is a list of all the known oxidation states of the chemical elements, excluding nonintegral values. The most common oxidation states are in bold. This table is based on Greenwood's,[1] with all additions noted. Oxidation state 0, which is found for all elements, is implied by the column with the element's symbol. The format of the table, based on one devised by Mendeleev in 1889, highlights some of the periodic trends. Ä1 H +1 He Li +1 Be +2 Ä1 B +1 +2 +3 [2] Ä4 Ä3 Ä2 Ä1 C +1 +2 +3 +4 Ä3 Ä2 Ä1 N +1 +2 +3 +4 +5 Ä2 Ä1 O +1 +2 Ä1 F Ne Ä1 Na +1 Mg +1 +2 [3] Al +1 +3 Ä4 Ä3 Ä2 Ä1 Si +1 +2 +3 +4 Ä3 Ä2 Ä1 P +1 +2 +3 +4 +5 Ä2 Ä1 S +1 +2 +3 +4 +5 +6 Ä1 Cl +1 +2 +3 +4 +5 +6 +7 Ar Ä1 K +1 Ca +2 Sc +1 +2 +3 Ä1 Ti +2 +3 +4 Ä1 V +1 +2 +3 +4 +5 Ä2 Ä1 Cr +1 +2 +3 +4 +5 +6 Ä3 Ä2 Ä1 Mn +1 +2 +3 +4 +5 +6 +7 Ä2 Ä1 Fe +1 +2 +3 +4 +5 +6 Ä1 Co +1 +2 +3 +4 +5 Ä1 Ni +1 +2 +3 +4 Cu +1 +2 +3 +4 Zn +2 Ga +1 +2 +3 Ä4 Ge +1 +2 +3 +4 Ä3 As +2 +3 +5 List of oxidation states of the elements 2 Ä2 Se +2 +4 +6 Ä1 Br +1 +3 +4 +5 +7 Kr +2 Rb +1 Sr +2 [4] [5] Y +1 +2 +3 Zr +1 +2 +3 +4 Ä1 Nb +2 +3 +4 +5 Ä2 Ä1 Mo +1 +2 +3 +4 +5 +6 Ä3 Ä1 Tc +1 +2 +3 +4 +5 +6 +7 Ä2 Ru +1 +2 +3 +4 +5 +6 +7 +8 Ä1 Rh +1 +2 +3 +4 +5 +6 Pd +2 +4 Ag +1 +2 +3 Cd +2 In +1 +2 +3 Ä4 Sn +2 +4 Ä3 Sb +3 +5 Ä2 Te +2 +4 +5 +6 Ä1 I +1 +3 +5 +7 Xe +2 +4 +6 +8 Cs +1 Ba +2 La +2 +3 Ce +2 +3 +4 Pr +2 +3 +4 Nd +2 +3 Pm +3 Sm +2 +3 Eu +2 +3 Gd +1 +2 +3 Tb +1 +3 +4 Dy +2 +3 Ho +3 Er +3 Tm +2 +3 Yb +2 +3 Lu +3 Hf +2 +3 +4 List of oxidation states of the elements 3 Ä1 Ta +2 +3 +4 +5 Ä2 Ä1 W +1 +2 +3 +4 +5 +6 Ä3 Ä1 Re +1 +2 +3 +4 +5 +6 +7 Ä2 Ä1 Os +1 +2 +3 +4 +5 +6 +7 +8 Ä3 Ä1 Ir +1 +2 +3 +4 +5 +6 [6] Pt +2 +4 +5 +6 Ä1 Au +1 +2 +3 +5 Hg +1 +2 +4 [7] Tl +1 +3 Ä4 Pb +2 +4 Ä3 Bi +3 +5 Ä2 Po +2 +4 +6 Ä1 At +1 +3 +5 Rn +2 [8] Fr +1 Ra +2 Ac +3 Th +2 +3 +4 Pa +3 +4 +5 U +3 +4 +5 +6 Np +3 +4 +5 +6 +7 Pu +3 +4 +5 +6 +7 Am +2 +3 +4 +5 +6 Cm +3 +4 Bk +3 +4 Cf +2 +3 +4 Es +2 +3 Fm +2 +3 Md +2 +3 No +2 +3 Lr +3 Rf +4 A figure with a similar format (shown below) was used by Irving Langmuir in 1919 in one of the early papers about the octet rule.[9] The periodicity of the oxidation states was one of the pieces of evidence that led Langmuir to adopt the rule. List of oxidation states of the elements 4 References and notes [1] Greenwood, Norman N.; Earnshaw, Alan. (1997), Chemistry of the Elements (2nd ed.), Oxford: Butterworth-Heinemann, ISBNÄ0080379419, p. 28. [2] The compound magnesium diboride, a known superconductor, is an example of boron in its Ä1 oxidation state. [3] Low-valent magnesium compounds with Mg(I) have been obtained using bulky ligands; see Green, S. P.; Jones C.; Stasch A. (December 2007). "Stable Magnesium(I) Compounds with Mg-Mg Bonds". Science 318 (5857): 1754Å1757. doi:10.1126/science.1150856. PMIDÄ17991827. [4] "Yttrium: yttrium(II) hydride compound data" (http:/ / www. webelements. com/ webelements/ compounds/ text/ Y/ H2Y1-13598351. html). WebElements.com. Retrieved 2007-12-10. [5] "Yttrium: yttrium(I) bromide compound data" (http:/ / www. openmopac. net/ data_normal/ yttrium(i) bromide_jmol. html). OpenMOPAC.net. Retrieved 2007-12-10. [6] Ir(Ä3) has been observed in Ir(CO) 3Ä; see Greenwood, Norman N.; Earnshaw, Alan. (1997), Chemistry of the Elements (2nd ed.), Oxford: 3 Butterworth-Heinemann, ISBNÄ0080379419 p.1117 [7] Hg4+ has been observed in mercury tetrafluoride; see Xuefang Wang; Lester Andrews; Sebastian Riedel; and Martin Kaupp (2007). "Mercury Is a Transition Metal: The First Experimental Evidence for HgF .". Angew. Chem. Int. Ed. 46 (44): 8371Å8375. doi:10.1002/anie.200703710. 4 PMIDÄ17899620.. [8] Rn2+ has been observed in radon difluoride; see Stein, L. (1970). "Ionic Radon Solution". Science 168 (3929): 362. doi:10.1126/science.168.3929.362. PMIDÄ17809133. and Kenneth S. Pitzer (1975). "Fluorides of radon and element 118". J. Chem. Soc., Chem. Commun., (18): 760b Å 761. doi:10.1039/C3975000760b. [9] Irving Langmuir. The arrangement of electrons in atoms and molecules. J. Am. Chem. Soc. 1919, 41, 868-934. doi:10.1021/ja02227a002 Article Sources and Contributors 5 Article Sources and Contributors List of oxidation states of the elements ÄSource: http://en.wikipedia.org/w/index.php?oldid=434858359 ÄContributors: Anoop.m, Axiosaurus, Difluoroethene, Eoghanacht, God Emperor, Icairns, Itub, J.delanoy, Lanthanum-138, Materialscientist, Mikeo, Minus198, Nergaal, Oxymoron83, Puppy8800, Qweeer, R8R Gtrs, Yoenit, 12 anonymous edits Image Sources, Licenses and Contributors Image:Langmuir valence.png ÄSource: http://en.wikipedia.org/w/index.php?title=File:Langmuir_valence.png ÄLicense: Public Domain ÄContributors: Irving Langmuir License Creative Commons Attribution-Share Alike 3.0 Unported http:/ / creativecommons. org/ licenses/ by-sa/ 3. 0/.
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