Wikipedia:Reference desk/Archives/Science/2020 September 18

= September 18 =

Energy from rusting
Roughly speaking how much energy, in Joules, is given off by completely rusting 1Kg of Iron? 2A01:E34:EF5E:4640:6149:84E9:11CE:A892 (talk) 09:47, 18 September 2020 (UTC)


 * The article on energy density has a handy table. Rust can have different compositions, but the "burned to iron(iii) oxide" row should be a decent enough approximation. 85.76.15.6 (talk) 10:52, 18 September 2020 (UTC)

Why are Pnictogen hydrides so poisonous?
Why are Pnictogen hydrides like ammonia,phosphine and arsine so poisonous?Acidic Carbon (Corrode)  13:23, 18 September 2020 (UTC)
 * Should there be a redirect: Pnictogen hydrides → Pnictogen hydride ? --2606:A000:1126:28D:31A8:66E0:89AA:D98E (talk) 16:48, 18 September 2020 (UTC)
 * Each one's article talks about its specific toxicity profile. At least phosphine, arsine, and stibine are quite explicit about what their mode of action is. DMacks (talk) 17:05, 18 September 2020 (UTC)
 * Ammonia is not so dangerous as the others. Its main issue is as a strong base. Animals have a way to deal with ammonia in the body. For humans it is to make urea. Graeme Bartlett (talk) 22:28, 19 September 2020 (UTC)
 * IP: No.  already links to Pnictogen hydrides (I CSDd the unnecessary redirect). See WP:LINK. —[  Alan M 1  (talk) ]— 07:04, 23 September 2020 (UTC)

Missing a hurricane
Hurricane Alice (December 1954) says that two cyclones, including a Category 2 hurricane, operationally went undetected in 1954. In a time before satellite pictures, how would meteorologists learn that they hadn't noticed a storm? 2601:5C6:8081:35C0:2C6E:461:D260:3BF (talk) 22:26, 18 September 2020 (UTC)
 * No source is cited for that specific statement, but José A. Colón's paper cited as a reference from the paragraph refers to another undetected hurricane in January 1951. Basically the answer to "how did they learn" seems to be that they reanalyzed the data they had already collected, when the storms were over with and they had time to do it. --174.88.168.23 (talk) 23:08, 18 September 2020 (UTC)