The promethium, the properties of atoms, chemical and physical properties.
Pm 61 Promethium
144,9127 1s2 2s2 2p6 3s2 3p6 4s2 3d10 4p6 5s2 4d10 5p6 6s2 4f5
The promethium — element of the periodic system of chemical elements of Mendeleev with atomic number 61. Located in the 3rd group (old classification — side subgroup of the third group), the sixth period of the periodic system. Belongs to the group of lanthanides.
General information
Properties of an atom
Chemical properties
Physical properties
Table of chemical elements of D. I. Mendeleev
General information
|
|
| Name |
The PM/ Promethium |
| Symbol |
Pm |
| Room at the table |
61 |
| Type |
Metal |
| Open |
D. Marin, L. Glendenin and Part of Coryell, USA, 1885 |
| Appearance, etc. |
Light-gray radioactive metal. Has no stable isotopes. |
| The contents in the earth’s crust |
0 %. In nature practically does not occur. Obtained by synthesis. |
| The contents in the ocean |
0 % |
Properties of an atom
|
|
| The atomic mass (molar mass) |
144,9127 and. E. M. (g/mol) |
| Electronic configuration |
1s2 2s2 2p6 3s2 3p6 3d10 4s2 4p6 4d10 5s2 5p6 6s2 4f5 |
| The radius of the atom |
183 PM |
Chemical properties
|
|
| Oxidation |
+3 |
| Valence |
+3 |
| Covalent radius |
199 PM |
| The radius of the ion |
(+3e)111 PM |
| Electronegativity |
1,1 (scale Pauling) |
| Energy of ionization (the first electron) |
536,0 kJ/mol (of 5.56 eV) |
| Electrode potential |
-2,29 In |
Physical properties
|
|
| Density (under normal conditions) |
Of 7.26 g/cm3 |
| Melting point |
1042 °C (1315 K) |
| Boiling point |
~3000 °C (~3273 K) |
| UD. the heat of fusion |
Of 7.13 kJ/mol |
| UD. heat of evaporation |
330,5 kJ/mol |
| Molar heat capacity |
Of 27.6 j/(K·mol) |
| Molar volume |
19,96 cm3/mol |
| The thermal conductivity (at 300 K) |
17.9 W/(m·K) |
| The electrical conductivity in the solid phase |
1,3×106 s/m |
| Superconductivity at a temperature of |
|
| Hardness |
|
| The lattice structure |
hexagonal |
| The lattice parameters |
a = the 3.65 Å, c = 11,65 Å |
| The ratio c/a |
3,19 |
| Debye Temperature |
|
Table of chemical elements of D. I. Mendeleev
