ThomsonB

=J.J. Thomson

=

JJ Thomson found proof of negativley charged particles that could be removed from an atom. He called these negativley charged particles electrons. He then proposed a model of an atom that was a positive sphere with electrons evenly spaced inside. Thomson and H. Nagaoka (Japanese scientist) believed that the atoms contained electrons, so something positive had to be within the atom to keep it neutral. Thomson decided that the rest of the matter had to be positively charged to maintain an electric neutrality. The name plum pudding came about because the picture made to describe the atom had the positively charged sphere (pudding) with electrons (plums) within it.

Plum Pudding



This model is also known as the Chocolate Chip Cookie or Blueberry Muffin Model. The food explanation is easy to understand, whereas the pudding, cookie, or muffin part are positivley charged and the plums, chocolate chips, or blueberries are negativley charged electrons.

[|_http://www.universetoday.com/38326/plum-pudding-model/__] []