Answer:
By 1920, physicists knew that most of the mass of the atom was located in a nucleus at its center, and that this central core contained protons. In May 1932 James Chadwick announced that the core also contained a new uncharged particle, which he called the neutron. Chadwick was born in1891 in Manchester, England.
Explanation:
He just change the placement or country
Answer:
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Explanation:
genus (pl. genera)
in the modern classification system, a subdivision of a family; includes one or more species of organisms
