|
|
| Atomic properties |
|---|
| Atomic number |
4 |
|---|
| Standard atomic weight |
9.012 182(3) |
|---|
| Electron configuration |
1s2 2s2 |
|---|
| Physical properties[1][2] |
|---|
| Melting point |
1278 °C (1551 K) |
|---|
| Boiling point |
1317 °C (1590 K) |
|---|
| Density |
1.848 g cm−3 (20 °C) |
|---|
| Electric resistivity |
4.46 µΩ cm |
|---|
| Chemical properties[2][3] |
|---|
| Electronegativity |
1.57 (Pauling) |
|---|
| Solubility in water |
insoluble, unreactive |
|---|
| Ionization energies[4] |
|---|
| 1st |
9.322 6277(13) eV
895.064 89(12) kJ mol−1 |
|---|
| 2nd |
18.211 eV
1757.1 kJ mol−1 |
|---|
| 3rd |
153.893 eV
14 848.4 kJ mol−1 |
|---|
| 4th |
217.713 ev
21 006.1 kJ mol−1 |
|---|
| Total |
399.139 eV
38 511.1 kJ mol−1 |
|---|
| Atomic radii[5][6] |
|---|
| Covalent radius |
96 pm |
|---|
| Ionic radius |
27 pm (Be2+, Td) |
|---|
| Thermodynamic properties[1][7] |
|---|
| Standard entropy |
9.50(8) J K−1 mol−1 |
|---|
| Enthalpy change of atomization |
324(5) kJ mol−1 |
|---|
| Entropy change of atomization |
136.275(3) J K−1 mol−1 |
|---|
| Enthalpy change of fusion |
15.51 kJ mol−1 |
|---|
| Hazards[8] |
|---|
| GHS pictograms |
  |
|---|
| GHS signal word |
DANGER |
|---|
| GHS hazard statements |
H350, H330, H301, H372, H319, H335, H315, H317 |
|---|
| Miscellaneous |
|---|
| CAS number |
7440-41-7 |
|---|
| EC number |
231-150-7 |
|---|
| Where appropriate, and unless otherwise stated, data are given for 100 kPa (1 bar) and 298.15 K (25 °C). | |
|
Beryllium (symbol: Be) is a chemical element, the lightest of the alkaline earth metals.
Notes and references
Notes
References
- ↑ 1.0 1.1 Beryllium. In NIST Chemistry WebBook; National Institute for Standards and Technology, <http://webbook.nist.gov/cgi/inchi/InChI%3D1S/Be>. (accessed 20 June 2010).
- ↑ 2.0 2.1 Greenwood, Norman N.; Earnshaw, A. Chemistry of the Elements; Pergamon: Oxford, 1984; pp 117–54. ISBN 0-08-022057-6.
- ↑ Allred, A. L. Electronegativity values from thermochemical data. J. Inorg. Nucl. Chem. 1961, 17 (3–4), 215–21. DOI: 10.1016/0022-1902(61)80142-5.
- ↑ Moore, Charlotte E. Ionization potentials and ionization limits derived from the analyses of optical spectra. Natl. Stand. Ref. Data Ser., (U.S. Natl. Bur. Stand.) 1970, 34, 1–22, <http://www.nist.gov/data/nsrds/NSRDS-NBS34.pdf>.
- ↑ Cordero, Beatriz; Gómez, Verónica; Platero-Prats, Ana E.; Revés, Marc; Echeverría, Jorge; Cremades, Eduard; Barragán, Flavia; Alvarez, Santiago Covalent radii revisited. Dalton Trans. 2008 (5), 2832–38. DOI: 10.1039/b801115j.
- ↑ Shannon, R. D. Revised effective ionic radii and systematic studies of interatomic distances in halids and chalcogenides. Acta Crystallogr. A 1976, 32 (5), 751–67. DOI: 10.1107/S0567739476001551.
- ↑ Cox, J. D.; Wagman, D. D.; Medvedev, V. A. CODATA Key Values for Thermodynamics; Hemisphere: New York, 1989. ISBN 0891167587, <http://www.codata.org/resources/databases/key1.html>.
- ↑ Index no. 004-001-00-7 of Annex VI, Part 3, to Regulation (EC) No 1272/2008 of the European Parliament and of the Council of 16 December 2008 on classification, labelling and packaging of substances and mixtures, amending and repealing Directives 67/548/EEC and 1999/45/EC, and amending Regulation (EC) No 1907/2006. OJEU L353, 31.12.2008, pp 1–1355 at p 340.
External links
