Scientists - Atomic structure

Question 1

JJ Thompson

Answer 1

Discovered electrons & isotopes

Cathode ray experiment

Question 2

Ernest Rutherford

Answer 2

Used alpha particles and found that atoms are mostly empty space and have a dense nucleus

Gold foil experiment

Question 3

John Dalton

Answer 3

Elements combine in fixed ratios which differ based on atomic weights of compounds being combined

Experimented with gases to make Dalton’s Atomic Theory

Question 4

Marie & Pierre Curie

Answer 4

Discover & isolate radium and polonium

Experimented with grinding pitchblend to find elements

Question 5

Henri Becquerel

Answer 5

Concluded that atoms could be radioactive

Experimented with fluorescent properties of uranium. Placed uranium salts on a photographic plate wrapped in black paper and saw that the plate was exposed in the shape of the uranium

Question 6

Robert Millikan

Answer 6

Determined the size of charge on an electron. Determined there is a smallest unit charge

Oil Drop experiment

Question 7

Neils Bohr

Answer 7

Discovered that electrons travel in separate orbits around the nucleus & that the number of electrons determines properties of an element

Developed theories & Bohr model based on knowledge of light

Question 8

Albert Einstein

Answer 8

Theory of relativity set base for atomic energy. Explained photoelectric effect and brownian motion
Atomic energy- E=mc^2

Question 9

Max Planck

Answer 9

Showed that there was a relationship between the amount of energy emitted and the frequency of electromagnetic radiation

Black body radiation

Question 10

Erwin Schrodinger

Answer 10

Created an electron cloud model with electrons in various orbitals

Used mathematical equations to determine the likelihood of finding an electron in a certain position