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535 BCE
Heraclitus
he believed everything was made of fire. made this discovery in the late 500 BC -
460 BCE
Democraus
he thought everything was made of tiny particles called atoms. ha made this discovery in the late 4th century BC -
384 BCE
Aritotle
there is really four elements air, earth,fire, and water he made this discovery in the 3rd century BC -
Dalton
he thought all matter is made from small particles called atoms.All atoms of a substance is the same size and mass.it cannot be broken down into smaller elements.all compound are whole numbers. they can only be separated using a chemical reaction. -
Thomson
used a cathode ray to prove that the atoms can be broken into smaller components. used the plum pudding which is a representation of the atom and the pudding was positively charged field and the plums were the electrons. -
Rutherford discovery
this was when he shot the particles at the golden foil and thought they would fly right through. he was wrong and they mostly missed. this helped further understand the atom because now we know that the atom's nucleus is positively charged. this adds to thomson's discovery because now we know that the atom's nucleus is positively charged. -
Bohr
he discovered that every different atom was has a different light associated with it. he used a line emission spectrum to conduct the experiments which was when you shoot a sharp light at the atom and it gives out a certain color scheme. he made this discovery in 1912 -
Chadwick
he figured out that there had to be a neutral particle around the nucleus for extra mass so he came up with the neutron in 1935 -
plum pudding
this was used to model the positively charged matter around the electrons and the electrons position . -
Cathode ray
the cathode ray was invented and used by thomson. the cathode ray was used to figure out that atoms have electons -
Emission spectra
line emission spectrum to conduct the experiments which was when you shoot a sharp light at the atom and it gives out a certain color scheme. this added to all the previous discoveries because they have never tested and they got to find out that every atom has their electrons in different places -
Schrodinger
he discovered that the electrons around the nucleus werent orbiting like planets but were in a cloud. he used a model that where the electrons were in a cloud and you cant place them perfectly in the right spot. he made this discovery in 1998