rhenium

American  

[ree-nee-uhm] / ˈri ni əm /

noun

Chemistry.

1. a rare metallic element of the manganese subgroup: used, because of its high melting point, in platinum-rhenium thermocouples. Re; 75; 186.2.

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rhenium British  

/ ˈriːnɪəm /

noun

1. a dense silvery-white metallic element that has a high melting point. It occurs principally in gadolinite and molybdenite and is used, alloyed with tungsten or molybdenum, in high-temperature thermocouples. Symbol: Re; atomic no: 75; atomic wt: 186.207; valency: –1 or 1–7; relative density: 21.02; melting pt: 3186°C; boiling pt: 5596°C (est)

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rhenium Scientific  

/ rē′nē-əm /

1. A very rare, dense, silvery-white metallic element with a very high melting point. It is used to make catalysts and electrical contacts. Atomic number 75; atomic weight 186.2; melting point 3,180°C; boiling point 5,627°C; specific gravity 21.02; valence 1, 2, 3, 4, 5, 6, 7.

2. See Periodic Table

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Etymology

Origin of rhenium

1920–25; < New Latin, equivalent to Latin Rhēn ( us ) Rhine + -ium -ium

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Example Sentences

See Examples For:

rhenium

The rhenium component helped hydrogen attach to and release from the catalyst surface, while the molybdenum sped up the splitting of water in the alkaline electrolyte.

From Science Daily ● May 18, 2026

As this happens, rhenium is left behind, which can be measured in water.

From Science Daily ● Nov. 14, 2023

Such demands necessitate the use of alloys of exotic metals such as rhenium, hafnium, nickel and titanium to provide the performance, efficiency and weight savings required for today's advanced aircraft engines.

From Nature ● Mar. 22, 2016

This later turned out to be element number 75, rhenium - another of the gaps in Mendeleev's table.

From BBC ● May 29, 2015

Plump, grizzled Dr. Fink has done other valuable work electroplating with tungsten and rhenium but he worked longest and hardest with chromium.

From Time Magazine Archive

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