Rhodium is a chemical element with an atomic number 45. Its relative atomic mass is 102.905 g/mol and it is represented by the symbol Rh. It is in group 9 and period 5 in the periodic table. Its electronic configuration is 1s2 2s2 2p6 3s2 3p6 3d10 4s2 4p6 4d8 5s1 ([Kr] 4d8 5s1). Rhodium has 45 electrons, 45 protons and 57 neutrons. It is in solid-state at STP and has a density of 12.41 g/cm3. Its melting point is 2237 K ?(1964 °C, ?3567 °F) and its boiling point is 3968 K ?(3695 °C, ?6683 °F). The electro negativity of Rhodium is 2.28 (Pauling scale) and it required 719.7 kJ/mol energy for its first ionization. Its oxidation states are −3, −1, 0, +1, +2, +3, +4, +5, and +6.
Rhodium has only one naturally occurring isotope Rhodium-103. It was discovered and first isolated by English chemist William Hyde Wollaston in 1804. Rhodium has a silver-white metallic appearance. It is chemically inert, hard and corrosion-resistant. It does not form oxide even when heated. But absorb Oxygen at its melting point which it releases on solidification. It is slightly dissolved in aqua regia and insoluble in nitric acid. It has a lower density than platinum but a higher melting point.
It is one of the rarest element and has an average estimated concentration of 0.0002 parts per million. It is extracted as a by-product from ores of silver, platinum, palladium and gold etc. The rarity increases its price for commercial uses. The main exporters of Rhodium are South Africa and Russia. South Africa produces 80% of world Rhodium. The annual world production is not more than 35 tonnes.
The following are some of the application of Rhodium.
It is used for corrosion resistance on other metals.
It is used in filters in mammography systems which are using X-rays.
Rhodium is used in spark plugs for aircraft and in the thermocouple.
It is used in jewelry and electroplated on white gold which gives it a reflective white surface.
In industrial processes, Rhodium catalysts are used such as the manufacture of certain silicone rubbers and conversion of methanol to produce acetic acid (Monsanto process).
What is rhodium used for?
It is used for corrosion resistance on other metals.
It is used in filters in mammography systems which are using X-rays.
Rhodium is used in spark plugs for aircraft and in the thermocouple.
It is used in jewelry and electroplated on white gold which gives it a reflective white surface.
In industrial processes, Rhodium catalysts are used such as the manufacture of certain silicone rubbers and conversion of methanol to produce acetic acid (Monsanto process).
What is the radius of a rhodium atom in angstroms (å)?
The atomic radius of Rhodium is 134 pm which is equal to 1.34 angstroms.
Where is rhodium found?
It is one of the rarest elements and has an average estimated concentration of 0.0002 parts per million on Earth's crust. It is extracted as a by-product from ores of silver, platinum, palladium, and gold, etc. The main exporters of Rhodium are South Africa and Russia. South Africa produces 80% of world Rhodium. The annual world production is not more than 35 tonnes.
