History of the atom

Question 1

Lavoisier 1789

Answer 1

The law of multiple proportions and mass cannot be created or destroyed:
* If two elements can form more than one compound together, the ratios of the masses of the second element will always be a whole number when combining with a fixed mass of the first element

Question 2

Dalton

Answer 2

• Atoms are indestructible, atomic theory, and law of multiple proportions

Question 3

Atomic theory

Answer 3

1. matter is composed of atoms, the smallest particle capable of participating in chemical reactions
2. elements contain only one type of atom, characteristic of that particular element
3. law of definite proportions
4. atoms are neither created nor destroyed during a chemical reaction, but rearranged

Question 4

mendeleev

Answer 4

arranged the elements to form the periodic table of elements

Question 5

goldstein

Answer 5

discovered positive particles

Question 6

Thomson

Answer 6

Discovered the electron using cathode rays. developed plum pudding model

Question 7

Rutherford

Answer 7

Gold foil experiment, alpha particles used to bombard gold foil, mass discovered at the center of the atom. The atom itself is mostly empty space

Question 8

Milikan

Answer 8

Determined the mass and charge of an electron with oil drop experiment

Question 9

bohr

Answer 9

electrons orbiting in shells around nucleus can be excited and moved to higher energy orbitals

Question 10

heisenberg

Answer 10

uncertainty principle, cannot know th energy and locatio of an electron at the same time

Question 11

Chadwick

Answer 11

discovered the neutron, necessary to balance the positive nucleus