Atomic+Discoveries+form+1900+to+1915

Robert Millikan 1868-1953

This American Physicist determined the charge of an electron by the "falling drop method" Oil was mystified into a chamber, some of the drops found their way through a hole in the bottom of the chamber. The drops of oil were allowed to reach terminal velocity. X-rays were shot at the oil drops, which changed the charge of the oil and the magnet cause the oil to stop falling or fall slower.

Henry Moseley 1887-1915

He discovered the charge of the nucleus of most atoms in 1914. He concluded, " The atomic number of an element is equal to the number of protons in the nucleus" This discovery helped change the periodic table by organization by charge instead of mass.

In WWII he helped his homeland, England, by volunteering for the Royal Engineers for the British army.