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Structure of atom (Part 1)

 Even as scientists were confirming the existence of the atoms, they discovered another layer of complexity below atoms. Atoms are made of still smaller particles. Studies of electricity suggested there needed to be something that you could transfer, that carried charge. It was the work of J.J. Thomson, Ernest Rutherford among others that led to advancements in our knowledge of atomic structure.

According to Dalton, an atom is an indivisible, hard,dense sphere. Atoms of the same element are alike. They combine in different ways to form compounds. In the light of Dalton's atomic theory, scientists performed a series of experiments. But in the late 1800's and early 1900's, scientists discovered new subatomic particles.

 •In 1886, Goldstein discovered positively charged particles called protons. 

•In 1897, J.J. Thomson found in an atom, the negatively charged particles known as electrons. It was established that electrons and protons are fundamental particles of matter. Based upon these observations Thomson put forth his “plum pudding” theory. He postulated that atoms were solid structures of positively charge with tiny negative particles stuck inside. It is like plums in the pudding.

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