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; rhod-, -ium

Example Sentences

Thieves target catalytic converters because they contain precious metals including rhodium, palladium and platinum.

From Los Angeles Times • Aug. 4, 2024

At that time, apparent supply-chain issues drove the price of rhodium, in particular, to a peak of nearly $29,000 per ounce.

From Seattle Times • Apr. 1, 2024

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

From Science Daily • Oct. 26, 2023

Catalytic converters, devices that reduce a vehicle’s harmful emissions, contain the precious rare metals platinum, rhodium and palladium, according to the National Insurance Crime Bureau, which tracks automobile thefts and insurance fraud.

From New York Times • Jun. 29, 2023

This substance is always native—it is always in the metallic state; and the metals with which it is found connected, and which are rarely found elsewhere, are palladium, rhodium, iridium, osmium, and ruthenium.

From The Chemical History of a Candle by Crookes, William, Sir