Atomic Theory

Question 1

1st to propose the idea of atoms. Meaning indivisible/uncuttable. Smallest unit of matter. Atoms have all different shapes.

Answer 1

Democritus(400 BCE)

Question 2

All matter is made of atoms. All atoms are 100% identical. Atoms are still uncuttable/indivisible. 1st atomic theory.

Answer 2

Dalton(1808)

Question 3

Discovered electrons with his Cathode Ray Experiment. Plum Pudding Model. Disproved Democritus.

Answer 3

Thomson(1897)

Question 4

Discovered positively charged, dense nucleus with his Gold Foil Experiment. Atoms are mostly empty space. Nuclear model. Disproved Thomson.

Answer 4

Rutherford(1911)

Question 5

Electrons are found in specific paths/energy levels called orbit around the nucleus. Planetary Model.

Answer 5

Bohr(1913)

Question 6

Electrons exist in general regions called electron clouds/orbitals. Quantum Mechanical Model. Wave -particle duality. Uncertainty Principle.

Answer 6

Schrodiner(1926)