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Anonymous users2024-02-11Iridium Englis Iridium Element Name: Iridium Elemental Atomic Weight: Element Type:
Metals Bulk Modulus of Elasticity: GPA 320 Enthalpy of Atomization: KJ Mol @25 628 Heat Capacity:
j (mol· k) thermal conductivity: w (m·k) 147 electrical conductivity: 10 6 (cm · heat of fusion:
kilojoules mol) heat of vaporization: (kJ moles) Atomic volume: (cubic centimeters mol) Density:
g cm3) The amount of elements in the universe: (ppm) The amount of elements in the sun: (ppm) The content of the earth's crust:
ppm) Oxidation state: main IR+3, IR+4 other IR-1, IR0, IR+1, IR+2, IR+5, IR+6 Crystal structure: The unit cells are face-centered cubic unit cells, and each unit cell contains 4 metal atoms.
Unit cell parameters: a = pm b = pm c = pm = 90° = 90° Mohs hardness: The rate at which sound propagates :
M S) 4825 Discovered by: Tennant Year of discovery: 1803 Discovery process:
In 1803, it was discovered by the Englishman Tennant. Element Description: The first ionization energy electron volts.
Silvery-white metal, hard and brittle. During thermal processing, as long as it is not annealed, it can be expanded into filaments and thin sheets; Once annealed, it loses its ductility and becomes hard and brittle. Density gram cm3.
The melting point is 2410 40, and the boiling point is 4130. Face-centered cubic crystals. The chemical properties are very stable.
Insoluble in acids. slightly soluble in aqua regia; It is slightly attacked by molten sodium hydroxide, potassium hydroxide and sodium dichromate. There is a strong tendency to form coordination compounds.
It is mainly found in osmium-iridium ore. It can be prepared by separating zinc from an osmium-iridium alloy obtained in the extraction of platinum.
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Anonymous users2024-02-10The Sun's nuclear transformation releases large quantities of rare metals.
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Anonymous users2024-02-09Located in the eighth group, viiiIt is a transition metal element, iridium is 1 part per million in the earth's crust, and is often dispersed together with platinum series in various ores of alluvial deposits and placer deposits.
Iridium is a platinum-based metal that is white like platinum with a hint of yellow. Iridium is hard and brittle and has a very high melting point, making it difficult to cast and plasticize. Iridium is the only metal that retains excellent mechanical properties in air above 1600 °C.
It has an extremely high boiling point, ranking 10th among all elements. Iridium exhibits superconductor properties below k.
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Anonymous users2024-02-08Iridium: atomic number 77, atomic weight, element name ** in Latin, the original meaning is "rainbow". In 1803, when the British chemist Tennant and the French chemist Descoty dissolved crude platinum with aqua regia, they discovered two new elements—osmium and iridium—from the black powder remaining at the bottom of the vessel.
Iridium is found in the earth's crust in parts per million and is often dispersed along with platinum series in various ores of alluvial and placer deposits. There are two isotopes in nature: iridium-191 and iridium-193.
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Anonymous users2024-02-07Iridium has extremely high chemical stability to acids, insoluble in acids, only spongy iridium will slowly dissolve in hot aqua regia, if it is iridium in a dense state, even if it is boiling aqua regia, it cannot be corroded; However, in a closed reactor under high temperature pressure, iridium is significantly corroded in aqua regia above 250°C. The mixed acid, which consists of 20 parts concentrated hydrochloric acid and 1 part concentrated nitric acid, is about 20 times more corrosive to iridium than aqua regia at the above temperature and pressure, so it is commonly used as a reagent for the digestion of metal iridium in chemical analysis.
1.It is the only metal that can withstand 150 degrees of pressurized aqua regia, and the use temperature can reach 200 degrees, other metals, tantalum can not be used above 150 degrees, and ruthenium and rhodium will be significantly corroded at about 140 degrees. Chromium begins to corrode at temperatures above atmospheric boiling.
2.The only metal with a corrosion rate of less than 190 years in 37% oxygenated hydrochloric acid.
3.It is one of the two metals that can be boiled at 338 degrees in concentrated sulfuric acid without corrosion (the other metal is ruthenium).
4.It is the only metal that is completely corrosion-free in a high concentration of phosphoric acid at 400 degrees.
5.It is the only metal that is completely corrosion-free in a 360 degree, 25MPa pressurized 5% H2SO4 + 5% HCl + 1% H2O2 high corrosive solution. (Under this working condition, even the corrosion rate of platinum is as high as more than 1mm per year).
In fact, of all the acids, bases, and salts, at least at atmospheric temperatures, only boiling magic acid can slowly corrode iridium.
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