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Platinum |
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Pronunciation | (PLAT-in-ǝm) |
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Appearance | grayish white |
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Standard atomic weight Ar, std(Pt) | 7002195084000000000♠195.084(9)[1] |
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Platinum in the periodic cairt |
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Atomic nummer (Z) | 78 |
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Group | group 10 |
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Period | period 6 |
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Block | d-block |
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Element category | Transeetion metal |
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Electron confeeguration | [Xe] 4f14 5d9 6s1 |
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Electrons per shell | 2, 8, 18, 32, 17, 1 |
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Pheesical properties |
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Phase at STP | solit |
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Meltin pynt | 2041.4 K (1768.3 °C, 3214.9 °F) |
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Bylin pynt | 4098 K (3825 °C, 6917 °F) |
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Density (near r.t.) | 21.45 g/cm3 |
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when liquid (at m.p.) | 19.77 g/cm3 |
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Heat o fusion | 22.17 kJ/mol |
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Heat o vapourisation | 469 kJ/mol |
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Molar heat capacity | 25.86 J/(mol·K) |
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Vapour pressur
P (Pa) |
1 |
10 |
100 |
1 k |
10 k |
100 k |
at T (K) |
2330 |
(2550) |
2815 |
3143 |
3556 |
4094 |
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Atomic properties |
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Oxidation states | −3, −2, −1, 0, +1, +2, +3, +4, +5, +6 (a mildly basic oxide) |
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Electronegativity | Pauling scale: 2.28 |
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Atomic radius | empirical: 139 pm |
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Covalent radius | 136±5 pm |
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Van der Waals radius | 175 pm |
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Spectral lines o platinum |
Ither properties |
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Naitural occurrence | primordial |
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Creestal structur | face-centred cubic (fcc) |
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Speed o soond thin rod | 2800 m/s (at r.t.) |
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Thermal expansion | 8.8 µm/(m·K) (at 25 °C) |
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Thermal conductivity | 71.6 W/(m·K) |
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Electrical resistivity | 105 n Ω·m (at 20 °C) |
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Magnetic orderin | paramagnetic |
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Young's modulus | 168 GPa |
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Shear modulus | 61 GPa |
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Bulk modulus | 230 GPa |
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Poisson ratio | 0.38 |
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Mohs haurdness | 4–4.5 |
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Vickers haurdness | 549 MPa |
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Brinell haurdness | 392 MPa |
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CAS Nummer | 7440-06-4 |
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History |
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Diskivery | Antonio de Ulloa (1735) |
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First isolation | Antonio de Ulloa (1735) |
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Main isotopes o platinum |
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Isotope |
Abundance |
Hauf-life (t1/2) |
Decay mode |
Product |
190Pt |
0.014% |
6.5×1011 y |
α |
186Os |
192Pt |
0.782% |
>4.7×1016 y |
α |
188Os |
193Pt |
syn |
50 y |
ε |
193Ir |
194Pt |
32.967% |
stable |
195Pt |
33.832% |
stable |
196Pt |
25.242% |
stable |
198Pt |
7.163% |
>3.2×1014 y |
α |
194Os |
β−β− |
198Hg |
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| references |