elements to memorize

hydrogen

H

Lithium

Li

Sodium

Na

Potassium

K

Plutonium

Pu

Titanium

Ti

Beryllium

Be

Magnesium

Mg

Calcium

Ca

Xenon

Xe

Barium

Ba

Chromium

Cr

Manganese

Mn

Cobalt

Co

Iron

Fe

Nickel

Ni

Zinc

Zn

Platinum

Pt

Copper

Cu

Iodine

I

Helium

He

Silver

Ag

Gold

Au

Mercury

Hg

Boron

B

Aluminum

Al

Carbon

C

Silicone

Si

Uranium

U

Tin

Sn

Lead

Pb

Nitrogen

N

Phosphorus

P

Arsenic

As

Oxygen

O

Sulfur

S

Krypton

Kr

Fluorine

F

Chlorine

Cl

Bromine

Br

Neon

Ne

Argon

Ar

dalton

realized law of multiple proportions, created billiard ball model

law of multiple proportions

matter always combines in ratios of whole numbers

billiard ball model

created by dalton, atoms one large, indivisible sphere, first model

plum pudding model

negatively charged electrons in positive substance, created by Thomson, second model

Thomson

used a cathode ray tube, used magnet to bend ray, more mass bent less, as well as faster particles, proved existence of negatively charged electrons, created billiard ball model of the atom

nuclear model

third model of an atom, dense positive charge in center, called the nucleus, created by rutherford

rutherford

gold foil experiment, shot alpha particles at really thin piece of gold, discovered most particles went through while some deflected at angles, concludes atom is mostly empty space with dense positive charge in center

planetary model

fourth model of the atom, electrons orbit the nucleus in distinct energy levels, made by bohr

bohr

explains emission spectra of hydrogen (the light emitted) based on quantized/specific energy levels, higher energy farther from the nucleus, moving between energy levels releases energy, which is turned into light, and vice versa

quantum/electron cloud model

electrons organized into orbitals (mathematical probability of where the electrons are likely to be found) around the nucleus, fifth and currently used model of atom, explains multi-electron emission spectra, allows electrons to be a wave or particle

millikan’s oil drop experiment

calculated charge on an electron, used negative plate and force of gravity to balance drop of oil in ionized air (so the electrons go into the air from the oil)

atomic mass

the total neutrons and protons

isotope

a different weight for the same element, due to a change in neutrons