rhodium

American  

[roh-dee-uhm] / ˈroʊ di əm /

noun

Chemistry.

1. a silvery-white metallic element of the platinum family, forming salts that give rose-colored solutions: used to electroplate microscopes and instrument parts to prevent corrosion. Rh; 102.905; 45; 12.5 at 20°C.

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rhodium British  

/ ˈrəʊdɪəm /

noun

1. a hard corrosion-resistant silvery-white element of the platinum metal group, occurring free with other platinum metals in alluvial deposits and in nickel ores. It is used as an alloying agent to harden platinum and palladium. Symbol: Rh; atomic no: 45; atomic wt: 102.90550; valency: 2–6; relative density: 12.41; melting pt: 1963±3°C; boiling pt: 3697±100°C

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rhodium Scientific  

/ rō′dē-əm /

1. A rare, silvery-white metallic element that is hard, durable, and resistant to acids. It is used as a permanent plating for jewelry and is added to platinum to make high-temperature alloys. Atomic number 45; atomic weight 102.905; melting point 1,966°C; boiling point 3,727°C; specific gravity 12.41; valence 2, 3, 4, 5, 6.

2. See Periodic Table

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Etymology

Origin of rhodium

From New Latin, dating back to 1804; see origin at rhod-, -ium

Example Sentences

Catalytic converters, which control exhaust emissions, are typically found in the undercarriage of a vehicle and contain precious metals including rhodium, palladium and platinum.

From Los Angeles Times • May 28, 2024

But demand will inevitably go back up once the prices of rhodium, palladium and platinum — metals used in the manufacture of catalytic converters — rise again, law enforcement officials and lawmakers say.

From Seattle Times • Apr. 1, 2024

The mined ore contains platinum, palladium and rhodium, three of the earth’s rarest, most expensive metals — and vital components in the millions of catalytic converters that reduce polluting emissions from gasoline-powered vehicles.

From New York Times • Nov. 15, 2023

Until now, similar catalysts have used expensive metals like platinum, rhodium, or iridium.

From Science Daily • Oct. 26, 2023

I think that oil of rhodium and oil of aniseed are very good to drop on the traps after setting, or to mix with the stuff with which the traps are covered.

From Full Revelations of a Professional Rat-catcher After 25 Years' Experience by Matthews, Ike