where is it used?
As  one of the catalysts in the three-way catalytic converters in automobiles.
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.
what is rhodocene? aA chemical compound with the formula [Rh(CH)]. for what purpose is it used? In radiotherapy for small tumours. can the salt be substituted? Yes what is the chemical element of rh? Rhodium who discovered it? William Hyde Wollaston what are some of its characteristics? It is a hard, silvery, durable metal that has a high reflectance.
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Rhodium [SEP] Introduction
It was discovered in 1803 by William Hyde Wollaston in one such ore, and named for the rose color of one of its chlorine compounds. 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. White gold is often plated with a thin rhodium layer to improve its appearance while sterling silver is often rhodium-plated for tarnish resistance.