General | States | Energies | Oxidation & Electrons |Appearance & Characteristics
Reactions | Other Forms |Radius | Conductivity | Abundance
Encyclopedia Britannica articles


Name Platinum Symbol Pt
atomic number 78 Atomic weight 195.09
Density @ 293 K 21.45 g/cm3 Atomic volume 9.10 cm3/mol
Group Trans. Met. discovered 1748


state (s, l, g) s
melting point 2045.2 K boiling point 4443 K
Heat of fusion 19.60 kJ/mol Heat of vaporization 510.0 kJ/mol
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1st ionization energy 870 kJ/mole electronegativity 2.28
2nd ionization energy 1791 kJ/mole electron affinity 205.3 kJ/mole
3rd ionization energy kJ/mole Specific heat 0.13 J/gK
heat atomization 565 kJ/mole atoms

Oxidation & Electrons

Shells 2,8,18,32,17,1 electron configuration [Xe] 4f14 5d9 6s1
minimum oxidation number 0 maximum oxidation number 6
min. common oxidation no. 0 max. common oxidation no. 4
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Appearance & Characteristics

structure fcc: face-centered cubic color silvery-white
uses jewelry, catalysts toxicity
hardness 4.3 mohs characteristics Inert, ductile


reaction with air none reaction with 6M HCl none
reaction with 6M HCl none reaction with 15M HNO3 none
reaction with 6M NaOH none
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Other Forms

number of isotopes 6 hydride(s) none
oxide(s) PtO2 chloride(s) PtCl2 PtCl4


ionic radius (2- ion) pm ionic radius (1- ion) pm
atomic radius 139 pm ionic radius (1+ ion) pm
ionic radius (2+ ion) 94 pm ionic radius (3+ ion) pm
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thermal conductivity 71.6 J/m-sec-deg electrical conductivity 94.34 1/mohm-cm
polarizability 6.5 A^3


source nickel ores (sulfides) rel. abund. solar system 0.127 log
abundance earth's crust -2.3 log cost, pure 4700 $/100g
cost, bulk 1200 $/100g
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World Wide Web presentation of Chemicool Periodic Table is © Copyright 1996-99 by David D. Hsu. Some data were provided by and used with the permission of JCE Software and is owned and copyright by the Division of Chemical Education, Inc. Additional data were provided by Perkin-Elmer through Peter Lykos of IIT. The information may not be redistributed without the permission of David Hsu or JCE Software.