Americium, properties of atom, chemical and physical properties.
Am 95 Americium
243*** 1s2 2s2 2p6 3s2 3p6 3d10 4s2 4p6 4d10 4f14 5s2 5p6 5d10 6s2 6p6 7s2 5f7
Americium — element of the periodic system of chemical elements D. I. Mendeleev, with atomic number 95. Located in the 3rd group (old classification — side subgroup of the third group), the seventh period of the periodic system. Belongs to the group of actinides.
General information
Properties of an atom
Chemical properties
Physical properties
Table of chemical elements of D. I. Mendeleev
General information
|
|
Name |
Americium/ Americium |
Symbol |
Am |
Room at the table |
95 |
Type |
Metal |
Open |
E. M. McMillan and Phillip H. Abelson, USA, 1940 |
Appearance, etc. |
Silvery-white radioactive metal |
The contents in the earth’s crust |
0 %. Obtained by synthesis. |
The contents in the ocean |
0 % |
Properties of an atom
|
|
The atomic mass (molar mass)*** |
243 and. E. M. (g/mol) |
Electronic configuration |
1s2 2s2 2p6 3s2 3p6 3d10 4s2 4p6 4d10 4f14 5s2 5p6 5d10 6s2 6p6 7s2 5f7 |
The radius of the atom |
173 PM |
Chemical properties
|
|
Oxidation |
+6, +5, +4, +3, +2 |
Valence |
+3, +4 |
Covalent radius |
180±6 PM |
The radius of the ion |
(+4e) 92 (+3e) 107 PM |
Radius van der Waals |
|
Electronegativity |
Of 1.3 (scale Pauling) |
Energy of ionization (the first electron) |
578 kJ/mol (6.0 eV) |
Electrode potential |
-0,90 V, -2,07 V, -1,95 IN |
Physical properties
|
|
Density (under normal conditions) |
13,67 g/cm3 |
Melting point |
1176 °C (1449 K) |
Boiling point |
2607 °C (2880 K) |
UD. the heat of fusion |
Of 14.39 kJ/mol |
UD. heat of evaporation |
238,5 kJ/mol |
Molar heat capacity |
25,85 j/(K·mol) |
Molar volume |
20,8 cm3/mol |
The thermal conductivity (at 300 K) |
10 W/(m·K) |
The electrical conductivity in the solid phase |
|
Superconductivity at a temperature of |
|
Hardness |
|
The lattice structure |
hexagonal |
The lattice parameters |
a = 3,468 Å, c = Å 11,24 |
Debye Temperature |
|
Note:
*** The value is the atomic mass for stable isotope.
Table of chemical elements of D. I. Mendeleev