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THEORY OF ATOM
77 the atom of the first has 1 electron, that of the second two, and so on, upto the atom of 92nd element which has 92 electrons
Hydrogen Atom
Hydrogen is the first of the 92 elements. It is a gas and was first discovered in 1756 by Cavendish as a distinct substance Its 'atom' is the lightest of all In the first part of the 19th century it was considered to be the primary particle of all the elcmonts, but later this was proved to be false. At present it is accepted to be an independent element the first of the 92 elements The internal structure of hydrogen atom revcals that there is a single positively charged particle called 'proton' as nucleus, and a single negatirely charged electron, rotating about at Thus, these two oppositely charged electric particles make up a hydrogen atom But since the positive charge of the nucleus is equal to the negative charge of the electron, the hydrogen atom as a whole is electrically neutral This is also the case with all the atoms of different elcrents--the number of electrons boing equal to the number of positively charged particles (protons) in its nucleus. The size and weight of all these have now been accurately determined and are given below
A hydrogen atom has a diamcter of 1'200,000,000 inch and its weight is 164/000,000,000,000,000,000,000,000 gramme
