uranium 235

noun

, Chemistry.

1. the radioactive uranium isotope having a mass number of 235, comprising 0.715 percent of natural uranium. When bombarded with neutrons it undergoes fission with the release of energy.

Word History and Origins

Origin of uranium 235¹

First recorded in 1935–40

Example Sentences

The more uranium 235 your nuclear fuel has, the smaller you can make your reactor—or your bomb, which is why the material is subject to such strict regulations.

From Scientific American

The Iranian images of the plant released last year show the assembly of the centrifuges — tall, thin machines that enrich, or concentrate, uranium’s rare component, uranium 235.

From Seattle Times

The deal allows research, which now has improved their breakout time down to a day or two, by means of rapid centrifuge enrichment of uranium 235.

From New York Times

By December 6, the spectrographers had accumulated their first measurable, if invisible, quantity of uranium 235—far from pure but at more than triple the concentration found in nature.

From Literature

It has enriched uranium to one part uranium 235 in five parts, not to one part in 20.

From New York Times