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Atom
,→Plum Pudding Model of the Atom
: [[John Dalton]] had his [[Scientific Theory|theory]] backed up by the discoveries of [[Robert Brown]] who discovered [[Brownian Motion]] showing that small invisible [[particle]]s were responsible for the apparent random motion of small visible [[particle]]s such as [[pollen]].
=====Plum Pudding Model of the Atom=====
: In 1897 [[J.J. Thompson]] discovered that there was a [[particle]] smaller than an [[atom]] which he named the [[electron]] after another [[scientist]] had [[hypothesis|hypothesised]] their existence. The [[electron]] was found to be around 1860 2000 times less [[mass]]ive than a [[Hydrogen]] [[atom]]. It was later realised that these [[electron]]s were responsible for [[Electrical Current|electrical current]] in [[metal]]s.: This led him, in 1904, to propose the [[Plum Pudding Model]] of the [[atom]] in which [[atom]]s were believed to be a solid ball of [[positive]] charge with [[electron]]s stuck inside to give an overall [[neutral]] charge to the [[atom]].
=====Nuclear Model of the Atom=====
: In 1909 [[Ernest Rutherford]] set two students to work on an experiment to probe the structure of the [[atom]] in the hope to determine if the [[Plum Pudding Model]] was correct.