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Period: to
Issac Newton
Issac Newton thought that there were small solid masses which were always in motion. This led scientists into finding out all about of what we know about atoms. -
Period: to
John Dalton
John Daltons theory was that elements combine at atomic levels in fixed ratios. This ratiowould change in compounds because of the different atomic weights of the elements. So John Dalton thought that the firstly pure elements are made of atoms. 2ndly atoms of an element are all the same in that element. 3rdly atoms of different elements can be told apart by their atomic weights 4thly atoms in elements combine to create chemical compounds. -
Period: to
Niels Bohr
Niels Bohr thought that the atom was the smallest particle with a positively charged nucleus in the middle and are surrounded by orbitting electrons. His big discovery in the atom was that electrons travel in seperate orbits around the nucleus. Also the number of electrons in the outer orbit determine the properties of an element. -
Period: to
Joseph John Tohmpson
Joseph John Tohmpson thought that the atom was a sphere with positive matter in the atom there are electrons in which are positioned by electrostatic forces. When he found out this he than realized that with this information he could find out how many electrons were in the atom. -
Period: to
Ernest Rutherford
Ernest Rutherford thought that an atom has a positive nucleus in the middle and is being surrounde by negative electrons. So this means that most of the mass of the atom is in the nucleus and the rest was mostly empty space. -
Period: to
James Chadwick
James Chawick thought that the atom had a neutrons knowing this he thought an atom was a nucleus with positively charged protons and neutral neutrons and is being surrounded by electrons.