People

Question 1

Aristotle

Answer 1

Matter is continuous (not made up of anything smaller)

Question 2

Boyle

Answer 2

Believed in the atomic nature of elements, no proof, 1st scientist w quantitative values for gases

Question 3

Daltons atomic theory

Answer 3

All matter atoms (no protons, neutrons, e)
All atoms of same element are same weight (no isotopes discovered)
Atoms cannot be divided/created/destroyed
Atoms combine in whole-number ratios to chemical compounds
In chemical rxn, atoms are combined/separated/rearranged

Question 4

Thomson

Answer 4

ELECTRONS= electron beam in cathode ray tube deflected by electrical/magnetic field, electron CHARGE:MASS ratio

Question 5

Lavoisier

Answer 5

Conservation of matter/mass

Question 6

Proust

Answer 6

Law of definite proportions, substance will always have same ratio of elements by mass (H2O is 2g:16g 1g:8g)

Question 7

Becquerel

Answer 7

Radioactivity

Uranium exposed photographic film

Question 8

Curies

Answer 8

Radioactivity

Rays produced by Uranium+Radium spontaneously by unstable nuclei

Question 9

Bohr

Answer 9

Electrons into shells/energy levels
Closer=less energy
2n^2=max # electrons per energy level if n=principal energy level
(n^2=max # orbitals per energy level)

Question 10

De Broglie

Answer 10

Quantum

Particles have wavelike characteristics (diffraction patterns)

Question 11

Milikan

Answer 11

Determine ELECTRONS charge and mass 9.11x10^-28 (1/1837th of lightest element H)
Oil drop test

Question 12

Rutherford

Answer 12

Empty space between nucleus and electrons (SMALL dense POSITIVE NUCLEUS), atomic structure
Gold foil experiment
Some alpha particles deflected through Au

Question 13

Moseley

Answer 13

Atomic numbers (# protons) via X-rays

Question 14

Planck

Answer 14

Quantum
Light has particle and wavelike characteristics
Energy not continuous, released in quanta aka photon (emission spectrum releases photon light)
E=hV

Question 15

Heisenberg and Schrodinger

Answer 15

Uncertainty principle
Impossible to know location AND velocity of subatomic particle at the same time
Wave-mechanical model: 3D e orbital cloud (unlike Bohr) treat e like waves, assign them quantum #s (sublevels, energy levels)

Question 16

Paulis exclusion principle

Answer 16

No two electrons can have the same set of 4 quantum numbers in an atom bc the 2 e in each orbital have opposite spin

Question 17

Hunds rule

Answer 17

Addition of electrons 1 orbital at a time

Aufbau Principle=e occupies lowest energy orbital

Question 18

Mendelev

Answer 18

1st periodic table

Atomic weight

Question 19

Democritus and Leucippus

Answer 19

The world is made up of empty space and tiny particles ATOMS

Question 20

Chadwick

Answer 20

Neutron, isotopes

Question 21

Einstein

Answer 21

Explained origin of energy released in nuclear charge

Question 22

Avogadro

Answer 22

Equal volumes of different gases contain equal numbers of molecules at the same temperature and pressure
(1 mole=22.4 L)

Question 23

Gay-Lussac

Answer 23

Gases in a rxn, volume of reactants and products are in small whole number ratios (1 vol H2+1 vol Cl2 = 2 vols HCl)

Question 24

Le Chatelier

Answer 24

When a system @ equilibrium is disturbed by a stress (temp, pressure, concentration change), it will try to minimize stress to attain equilibrium