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Atom
,→Dalton Model of the Atom
: An ancient Greek philosopher called [[Democratus]] first proposed that matter was made of [[atom]]s. He reasoned that if you keep cutting something in half eventually you will reach part of it which cannot be cut into smaller piece. The ancient Greek word for 'uncuttable' was [[atom]].
====Dalton Model of the Atom====
: It wasn't until the early 1800s that there was an [[Scientific EvideneEvidence|evidence]] based [[Scientific Theory|theory]] of the existence of an [[atom]]. It was proposed by [[John Dalton]] who suggested [[atom]]s were small [[sphere|spherical]] [[object]]s.
: [[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 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.