Rhodium and Platinum - Comparison - Properties

This article contains comparison of key thermal and atomic properties of rhodium and platinum, two comparable chemical elements from the periodic table. It also contains basic descriptions and applications of both elements. Rhodium vs Platinum.

rhodium and platinum - comparison

Compare rhodium with another element

Compare platinum with another element

Rhodium and Platinum – About Elements

Rhodium

Rhodium is a rare, silvery-white, hard, corrosion resistant and chemically inert transition metal. It is a noble metal and a member of the platinum group.

Platinum

Platinum is a dense, malleable, ductile, highly unreactive, precious, silverish-white transition metal. Platinum is one of the least reactive metals. It has remarkable resistance to corrosion, even at high temperatures, and is therefore considered a noble metal. Platinum is used in catalytic converters, laboratory equipment, electrical contacts and electrodes, platinum resistance thermometers, dentistry equipment, and jewelry.

Rhodium in Periodic Table

Platinum in Periodic Table

Source: www.luciteria.com

Rhodium and Platinum – Applications

Rhodium

The element’s major use (approximately 80% of world rhodium production) is as one of the catalysts in the three-way catalytic converters in automobiles. Because rhodium metal is inert against corrosion and most aggressive chemicals, and because of its rarity, rhodium is usually alloyed with platinum or palladium and applied in high-temperature and corrosion-resistive coatings. In nuclear reactors, rhodium-based detectors are often used for incore neutron flux measuring.

Platinum

Platinum is primarily an industrial metal. It is a critical material for many industries and is considered a strategic metal. Platinum is used as a catalyst, platinum is mostly found in vehicle catalytic converters that reduce toxic exhaust chemicals, and also in fuel cells to increase efficiency. The most common use of platinum is as a catalyst in chemical reactions, often as platinum black. In catalytic converters, platinum allows the complete combustion of low concentrations of unburned hydrocarbons from the exhaust into carbon dioxide and water vapor. Platinum has been used in thermocouple devices that measure temperature with high accuracy. Platinum is a component in magnetic coatings for high-density hard disk drives and some of the newer optical storage systems.

Rhodium and Platinum – Comparison in Table

Element	Rhodium	Platinum
Density	12.45 g/cm3	21.09 g/cm3
Ultimate Tensile Strength	950 MPa	150 MPa
Yield Strength	N/A	70 MPa
Young’s Modulus of Elasticity	380 GPa	168 GPa
Mohs Scale	6	3.5
Brinell Hardness	1100 MPa	400 MPa
Vickers Hardness	1246 MPa	550 MPa
Melting Point	1964 °C	1772 °C
Boiling Point	3695 °C	3827 °C
Thermal Conductivity	150 W/mK	72 W/mK
Thermal Expansion Coefficient	8.2 µm/mK	8.8 µm/mK
Specific Heat	0.242 J/g K	0.13 J/g K
Heat of Fusion	21.5 kJ/mol	19.6 kJ/mol
Heat of Vaporization	493 kJ/mol	510 kJ/mol