"McMillan's initial work there involved attempting to measure the magnetic moment of the proton, but he was beaten to it by Otto Stern and Immanuel Estermann." - This is a bit too colloquial in my opinion.
Y Tried to re-word it. Hawkeye7 (talk) 21:40, 22 October 2015 (UTC)[reply]
"This was mixed with hydrogen and oxygen to produce water, with was then collected with calcium chloride." - This sentence needs attention.
" Radioactivity was found concentrated in the calcium chloride, proving that it was in the oxygen." - Calcium chloride does not contain oxygen so is this oxygen in the form of water of crystallization or what?
I was unaware that uranium had been named after Uranus so perhaps you should spell out the reason for naming the new element neptunium more clearly.
Y Sure. I thought it was pretty well known. Had to double-check that the original source covers this. I was surprised to discover that a neutron has a magnetic moment, despite having no charge. Hawkeye7 (talk) 21:40, 22 October 2015 (UTC)[reply]
"The departure of McMillan was caused by the outbreak of World War II in Europe." - This is a new section and this statement is a bit stark. How about prefacing it with "The reason for McMillan's not continuing with this research was ..." or somesuch.
I sought advice from FunkMonk on the image and my understanding of his reply is that it is OK to use the image. I find that the article is well written and complies with MOS guidelines on prose quality and structure, is suitably cited to reliable sources, is neutral and is stable. I believe it meets the GA criteria. Cwmhiraeth (talk) 13:07, 23 October 2015 (UTC)[reply]