Chromium
| Latin name | Chromium |
| English name | Chromium |
| chemical symbol | Cr |
| atomic number | 24 |
| relative atomic mass | 51,9961 |
| period | 4 |
| group | VI.B |
| classification | transition metals |
| discovery year | 1797 |
| discoverer | L. N. Vauquelin |
| melting point [°C] | 1857 |
| boiling point [°C] | 2672 |
| density [g cm-3] | 7,19 |
| density at melting point [g cm-3] | 6,3 |
| electronegativity [Pauling] | 1,66 |
| oxidation states | I - VI |
| electron configuration | [Ar]3d5 4s1 |
| atomic radius [pm] | 166 |
| covalent radius [pm] | 127 |
| specific heat [J g-1K-1] | 0,45 |
| heat of fusion [kJ mol-1] | 16,9 |
| thermal conductivity [W m-1 K-1] | 93,9 |
| el. conductivity [S m-1] | 7,9.106 |
| 1. ionizing potential [eV] | 6,7666 |
| 2. ionizing potential [eV] | 16,5 |
| 3. ionizing potential [eV] | 30,96 |
| Mohs hardness | 8,5 |
| Vickers hardness [MPa] | 1060 |
| Brinell hardness [MPa] | 1120 |
| shear modulus [GPa] | 115 |
| Young's modulus [GPa] | 279 |
| point of superconductivity [K] | - |
| state at normal conditions | solid |
Resources
- BARTHELMY, David. Mineral Species containing Chromium. In: Mineralogy database [online]. 2010 [cit. 2012-09-10]. Available from: http://webmineral.com/
- BRITISH GEOLOGICAL SURVEY. 2012. European Mineral Statistics 2006-10. Keyworth, Nottingham: British Geological Survey. ISBN 978-0-85272-698-3
- HUSTED, Robert; et al. Chromium. In: LOS ALAMOS NATIONAL SECURITY. Los Alamos National Lab [online]. 2011 [cit. 2012-08-30]. Available from: http://periodic.lanl.gov/
- MELLOR, Joseph. Comprehensive Treatise on Inorganic and Theoretical Chemistry. Vol. 11. Londýn: Longmans, Green & Co., 1931.
- PAPP, John. Chromium. In: U.S. GEOLOGICAL SURVEY. Mineral Commodity Summaries [online]. 2013 [cit. 2013-03-03]. Available from: http://minerals.usgs.gov/
- REMY, Heinrich. Anorganická chemie - II. díl. 2. české vydání, dotisk. Praha: SNTL 1972, s. 151-185
- STARÝ, Jaromír; SITENSKÝ, Ivo; HODKOVÁ, Tereza. Surovinové zdroje České republiky - Nerostné suroviny 2011. In: Česká geologická služba. Surovinové zdroje v ČR [online]. 2011 [cit. 2012-07-25]. Available from: http://www.geology.cz/
- TICHÝ, Miloň. Toxikologie pro chemiky. 1. vyd. Praha: Karolinum, 1998, ISBN 80-7184-625-2.
© 2009-2015 | www.prvky.com | kontakt
