Platinum

of these articles is concerned with the chemical element platinum, for the honor for many sold clay/tone carriers sees platinum record.
Characteristics
iridium - platinum - gold
Pd
Pt
DS

[Xe] 4f 14 5d 9 6s 1
,195
78
Pt

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generally
name, symbol, ordinal number platinum, Pt, 78
series of transition metals
group, period, block 10 (VIIIb), 6, D
appearance grey-white
proportion at the Earth's shell 5· 10 -7 %
atomically
atomic mass 195.078
atomic radius (computed) 135 (177) pm
Kovalenter radius 128 pm
van the Waals radius 175 pm
Elektronenkonfiguration [Xe] 4f 14 5d 9 6s 1
electrons per energy level 2, 8, 18, 32, 17, 1
1. Ionization energy 870 kJ/mol
2. Ionization energy 1791 kJ/mol
physically
state of aggregation firmly
modifications -
crystal structure cubically face-centered
density (Mohshärte) 21450 kg/m 3 (4,3)
magnetism paramagnetic
melting point 2045 K (1772 °C)
boiling point 4100 K (3827 °C)
molecular volume 9,1 · 10 -6 m 3 /mol
heat of vaporization 510 kJ/mol
heat of fusion 19.6 kJ/mol
steam pressure 0.0312 Pa at 2045 K
speed of sound 2680 m/s with 293,15 K
specific thermal capacity 130 j (kg · K)
Electrical conductivity 9,66 · 10 6 S /m
heat conductivity 71.6 w (m· K)
Electron affinity 5.7 - 6.35 eV
chemically
oxidation conditions of 0, +2, +4
oxides (basicity) PtO, PtO 2 (easily basic)
Normalpotenzial 1.118 V (Pt 2+ + 2e - → Pt)
Elektronegativität of 2.28 (Pauling scale)
isotopes
ISO NH radioactive half-life DM DE M eV DP
188 Pt {syn.} 10.2 D ε 0.507 188 IR
189 Pt {syn.} 10.87 h ε 1.971 189 IR
190 Pt 0.01% 6,5 · 10 11 A α 3.249 186 OS
191 Pt {syn.} 2.96 D ε 1.019 191 IR
192 Pt 0.79% Pt 193 Pt are stable {
syn. with 114 neutrons} 50 A ε 0.057 193 IR
194 Pt 32.9% Pt 195 Pt 33.8% are stable
with 116 neutrons Pt is stably with 117 neutrons
196 Pt 25.3% Pt is stably with 118 neutrons
197 Pt {syn.} 19.8915 h β - 0.719 197 outer ones
198 Pt 7.2% Pt 199 Pt are stable {
syn. with 120 neutrons} 30,80 min β - 1.702 199 outer ones
200 Pt {syn.} 12.5 h β - 0.660 200 outer
NMR characteristics
195 Pt
nuclear spin 1/2
gamma/ wheel/T 5,751 · 10 7
sensitivity 0.00994
Larmorfrequenz with B = 4.7 T 43 MCycles per second
as far as possible and common, SI-UNITs are used.
If not differently notes,
the indicated data apply with standard conditions.


Platinum is a chemical element in the periodic system of the elements with the symbol Pt and the ordinal number 78.

Platinum is a heavy,forgeable, flexible, noble, grey-white transition metal. Platinum is very corrosion resistant and for the production of decoration goods, laboratory instruments, tooth implants, contact materials and catalysts is used.

Platin-Blech
Platin-Blech


table of contents

history

platinum already before the discovery America by Kolumbus by the Indians of South America one used. The name is derived from the Spanish word platina, the reduction form from plata “silver”. The first EuropeanMention comes from the Italian human Julius Caesar Scaliger (1484-1558). It describes a mysteriöses white metal, which extracted itself from all fusion attempts. A description in more detail of the characteristics is in to 1748 there a published report of Antonio Ulloa. 1750 placedthe English physician William Brownrigg cleaned metal ago.
Due to the high fusing temperature of 1772 °C platinum long time could be forged only in the white-hot condition. 1856 erschmolz the German pharmacist and chemist Wilhelm Carl Heraeus platinum in a detonating gas flame andjustified with this technology a platinum melt. End 19. Century became approx. 1000 kg metal processes.

the largest promotion nations

the platinum producer most meaning with distance South Africa is followed, of the Russian federation (above all the northern Urals).

The largest promotion nations (2003)
source: Trade paper the world in figures (2005)
rank country deliveries
(in t)
1 South Africa 140
2 Russian Föd. 70
3 Canada 18,5
The 4 USA 4,2
5 Colombia 1,4
6 Simbabwe 1,3

productionand production

metallic platinum (platinum soaps) is not practically any longer diminished today. There are platinum mines only in South Africa (Transvaal). Sources of platinum are also the non-ferrous metal production (copper and nickel) in Sudbury (Ontario) and Norilsk (Russia). Here metals of group of platinum result as by-product. AsPlatinum beside metal designates one five metals, which resemble platinum in such a way in their chemical behavior that the separation and pure representation made originally large difficulties. 1803 was discovered iridium , osmium , palladium , rhodium; 1844 followed ruthenium.

Characteristics

very and soft heavy metal corrosion resistant and the forgeable shows in the pure, polished condition the so-called. Dark gloss. Both hydrogen and oxygen and other gases are bound by platinum in the activated condition. It possesses therefore very remarkable catalytic characteristics; Hydrogenand react to oxygen explosively with one another in its presence to water. However platinum catalysts become fast by aging and impurities inactively (poisons).
The high durability and approach stability and rarity are particularly suitable platinum for the production of high-quality decoration goods.
Platinum shows, like alsothe other metals of group of platinum, a contradictory behavior. On the one hand it is precious metal-typically chemically slowly-acting, on the other hand highly reactive, catalytic-selectively in relation to certain substances and reaction conditions. Also at high temperatures platinum shows a stable behavior. It is interesting therefore for many industrielle applications.
In Salt and nitric acid are insoluble it. It is attacked by aqua regia under formation of red-brown Hexachloroplatin (IV) - acid. Also of alkali, peroxide, nitrate, cyanide and other salt melts platinum is attacked. Many metals form iron, nickel, copper with platinum alloys, for example, Cobalt, gold, tungsten, gallium, tin, etc. Particularly to emphasize it is that platinum reacts partially under connecting formation with hot sulfur , phosphorus , boron , silicon , carbon in each form, i.e. also inare called flame gases. Also many oxides react with platinum, why also only certain materials can be used as crucible material. When melting the metal with for example propane - oxygen must be worked therefore with more neutral to weak-oxidizing flame. Best possibility is the flame-freeelectrical-inductive heating of the Schmelzgutes in zircon oxide ceramics.

use

due to their availability and the outstanding characteristics platinum and platinum alloys are suitable outstanding for numerous different operational areas. Like that platinum is a favored material for the production of laboratory instruments. There platinumno flame coloration produced, e.g. become. thin platinum wires uses, in order to hold material samples into the flame of a Bunsen burner.

Platinum is used beyond that into almost difficult-to-understand number of ranges:

the international kilogram prototype, which is kept in a safe deposit of the international office for weights and mass (BIPM) in Sèvres with Paris, consists of an alloy of 90% platinum and10% iridium.
Of the same alloy consists international meter prototype of 1889, which defined meters until 1960 . For 2005 the consumption of platinum for the catalyst production on 3,86 millions becomes Ounces estimated.

safety references

platinum is normally not health-endangering. Its connections should be regarded as highly toxic. Some platinum connections (e.g.Cisplatin, Carboplatin) are used to the chemotherapy against cancer.

connections

  • platinum (VI) - oxide (PtO 3)
  • platinum (II) - chloride (PtCl 2)
  • Tetrachloroplatin (II) - acid (H 2 PtCl 4)
  • Hexachloroplatin (IV) - acid (H 2 PtCl 6)
  • platinum (IV) - fluoride (PtF 4)
  • platinum (V) - fluoride (PtF 5)
  • platinum (VI) - fluoride (PtF 6)
  • platinum (II) - bromide (PtBr 2)
  • platinum (IV) - bromide (PtBr 4)
  • platinum (II) - iodid (PtI 2)
  • platinum (IV) - iodid (PtI 4)

an example of a connectionwith platinum in the Oxidationstufe 0 Tetrakis

  • (triphenylphosphin) is platinum (Pt (PPh 3) 4)

connections with SI (z. B. for infrared cameras)

  • PtSi
  • Pt 2 SI
  • Pt 3 SI

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