|
Rhodium |
---|
Pronunciation | (ROH-dee-əm) |
---|
Appearance | silvery white metallic |
---|
Standard atomic weight Ar, std(Rh) | 7002102905490000000♠102.90549(2)[1] |
---|
Rhodium in the periodic cairt |
---|
|
Atomic nummer (Z) | 45 |
---|
Group | group 9 |
---|
Period | period 5 |
---|
Block | d-block |
---|
Element category | Transeetion metal |
---|
Electron confeeguration | [Kr] 4d8 5s1 |
---|
Electrons per shell | 2, 8, 18, 16, 1 |
---|
Pheesical properties |
---|
Phase at STP | solit |
---|
Meltin pynt | 2237 K (1964 °C, 3567 °F) |
---|
Bylin pynt | 3968 K (3695 °C, 6683 °F) |
---|
Density (near r.t.) | 12.41 g/cm3 |
---|
when liquid (at m.p.) | 10.7 g/cm3 |
---|
Heat o fusion | 26.59 kJ/mol |
---|
Heat o vapourisation | 494 kJ/mol |
---|
Molar heat capacity | 24.98 J/(mol·K) |
---|
Vapour pressur
P (Pa) |
1 |
10 |
100 |
1 k |
10 k |
100 k |
at T (K) |
2288 |
2496 |
2749 |
3063 |
3405 |
3997 |
|
Atomic properties |
---|
Oxidation states | −3, −1, 0, +1,[2] +2, +3, +4, +5, +6 (an amphoteric oxide) |
---|
Electronegativity | Pauling scale: 2.28 |
---|
Atomic radius | empirical: 134 pm |
---|
Covalent radius | 142±7 pm |
---|
Spectral lines o rhodium |
Ither properties |
---|
Naitural occurrence | primordial |
---|
Creestal structur | face-centred cubic (fcc) |
---|
Speed o soond thin rod | 4700 m/s (at 20 °C) |
---|
Thermal expansion | 8.2 µm/(m·K) (at 25 °C) |
---|
Thermal conductivity | 150 W/(m·K) |
---|
Electrical resistivity | 43.3 n Ω·m (at 0 °C) |
---|
Magnetic orderin | paramagnetic[3] |
---|
Young's modulus | 380 GPa |
---|
Shear modulus | 150 GPa |
---|
Bulk modulus | 275 GPa |
---|
Poisson ratio | 0.26 |
---|
Mohs haurdness | 6.0 |
---|
Vickers haurdness | 1246 MPa |
---|
Brinell haurdness | 1100 MPa |
---|
CAS Nummer | 7440-16-6 |
---|
History |
---|
Diskivery | William Hyde Wollaston (1804) |
---|
First isolation | William Hyde Wollaston (1804) |
---|
Main isotopes o rhodium |
---|
Isotope |
Abundance |
Hauf-life (t1/2) |
Decay mode |
Product |
99Rh |
syn |
16.1 d |
ε |
99Ru |
γ |
- |
101mRh |
syn |
4.34 d |
ε |
101Ru |
IT |
101Rh |
γ |
- |
101Rh |
syn |
3.3 y |
ε |
101Ru |
γ |
- |
102mRh |
syn |
2.9 y |
ε |
102Ru |
γ |
- |
102Rh |
syn |
207 d |
ε |
102Ru |
β+ |
102Ru |
β− |
102Pd |
γ |
- |
103Rh |
100% |
- |
(SF) |
|
105Rh |
syn |
35.36 h |
β− |
105Pd |
γ |
- |
|
Decay modes in parentheses are predictit, but hae nae yet been observed |
| references |