Talk:Uranium-235

isotopes

When was it known that only U235 fissions with thermal neutrons? I believe it was a significant time after fission was known, but am not sure for now. Gah4 (talk) 16:12, 30 June 2020 (UTC)

I am certainly not qualified to answer this, but the final paragraph in the left-hand column of page 891 here might be useful. Wtmitchell (talk) (earlier Boracay Bill) 15:12, 24 July 2020 (UTC)

OK, January 1939 for the discovery, and December 1942 for the first reactor. The reactor was designed with a moderator, because they knew by then it would allow neutrons to find U235 before (too many) were absorbed by U238. That is about four years. Gah4 (talk) 17:50, 24 July 2020 (UTC)

coal

A comparison with coal might be nice, and there should be plenty of WP:RS for it. Comparing atom for atom, C12 vs. U235, though, isn't very useful. Usually the comparison is by weight, I am not sure now if it is for 3.5% enriched, or how it is done. Without looking, though, I believe that there should be such a source. I do agree with removing the one just removed. Gah4 (talk) 22:30, 23 July 2020 (UTC)

Neutron capture

Intro says sometimes neutron capture forms U-236 but this seems dubious and has no reference and is not mentioned in the rest of the article. (Ground state U-236 has a long half life.) - Rod57 (talk) 09:46, 21 April 2021 (UTC)

It sounds familiar, but I don't know where I might have seen it. That would be more likely at lower neutron energy. Gah4 (talk) 19:30, 21 April 2021 (UTC)

OK, Uranium-236 says 18% for thermal neutrons. Gah4 (talk) 19:40, 21 April 2021 (UTC)