This collection presents 8 Chemical Elements that start with R, spanning from “Radium” to “Rutherfordium”. These elements are mostly metals used in medicine, industry, alloys, catalysts, and scientific research. See the A–Z index for other letters.
Chemical Elements that start with R are the set of elements whose names begin with the letter R. Notable example: radium helped launch modern radiotherapy, and Rutherfordium honors physicist Ernest Rutherford.
Below you’ll find the table with [COLUMN_NAMES]
Atomic number: Shows each element’s position on the periodic table so you can see its relative order.
Element: Gives the standard name so you can identify the element and match it to common usage.
Atomic weight: Shows the standard atomic weight with three decimals so you can compare mass among elements.
Discovery year: Lists the year or “Antiquity” to show historical context for when each element became known.
Quick note: many R elements are heavy transition metals or radioactive. This explains their common uses in high-temperature alloys, catalysts, medicine, and scientific research.
Chemical Elements that start with R
| Element | Atomic number | Atomic weight (u) | Discovery year | Description |
|---|---|---|---|---|
| Radium | 88 | 226.025 | 1898 (Curie, France) | Highly radioactive alkaline-earth discovered by the Curies; historically used in luminous paints and early radiotherapy (IUPAC/NIST) |
| Radon | 86 | 222.018 | 1900 (F. Dorn, Germany) | Colorless, radioactive noble gas from uranium/radium decay chains; indoor air health hazard, short-lived (IUPAC/NIST) |
| Rhenium | 75 | 186.207 | 1925 (Noddack, Berg & Tacke, Germany) | Rare, high-melting refractory metal used in jet-engine superalloys and catalysts (IUPAC/NIST) |
| Rhodium | 45 | 102.906 | 1803 (W. H. Wollaston, UK) | Rare, silvery-white noble metal used in catalytic converters and jewelry plating; very corrosion-resistant (IUPAC/NIST) |
| Rubidium | 37 | 85.468 | 1861 (Bunsen & Kirchhoff, Germany) | Soft, silvery alkali metal found in minerals; used in research, atomic clocks, and specialty glass (IUPAC/NIST) |
| Ruthenium | 44 | 101.072 | 1844 (K. Klaus, Russia) | Hard, silvery transition metal used to harden platinum, in electrical contacts, and some catalysts (IUPAC/NIST) |
| Rutherfordium | 104 | 267.000 | 1964–1969 (Dubna, USSR; Berkeley, USA) | Synthetic transactinide named for Ernest Rutherford; produced in accelerators. Atomic mass shown as representative mass number (IUPAC) |
| Roentgenium | 111 | 282.000 | 1994 (GSI, Germany) | Synthetic element named for Wilhelm Röntgen; created in heavy-ion collisions, only short-lived isotopes known (IUPAC) |