history of an atom- scientists (unit 2)

Question 1

antoine lavosier

Answer 1

-law of conservation of mass
-mass of reactants = mass of the products
-chemical reactions
-no model

Question 2

john dalton

Answer 2

-different elements have different properties (determined by atoms)
-chemical reactions:
experiments with properties of gas to see the speed and movement of particles
-filled circle model

Question 3

j.j thomson*

Answer 3

-electrons are apart of atoms
-cathode ray experiment with magnetic plates to see where electrons would be attracted to
-plum pudding model

Question 4

ernest rutherford*

Answer 4

-electrons orbit a small, dense, positively charged nucleus made of protons and neutrons
-gold foil experiment: shooting alpha particles (tiny positive charged particles)
- proved that most of the atom was empty space, some particles got deflected because of nucleus
-nuclear model/planetary

Question 5

niels bohr

Answer 5

-orbits of electrons are at fixed “quantized” energy levels often calls shells/orbitals
-spectrum of light given of when absorption of electrons become excited and move up energy levels, then move back down
-( frank herst) passed electrons through gas tube which showed discreet amounts of energy
-planetary model of the atom