Unit of matter, the smallest unit of a chemical element
Atom
Lithium
Li .
14 3-
N
7
P = 7
E = 10
N = 7
Electron Orbitals
Neils Bohr
Atomic Number =
Number of Protons
A particle with a positive charge
Proton
Radium
.
Ra .
9 +2
Be
4
P = 4
E = 2
N = 5
Democritus
Protons + Neutrons =
Mass Number
Atoms of the same element, but different number of neutrons
Isotope
Krypton
..
: Kr :
..
23 +1
Na
11
P = 11
E = 10
N = 12
Gold Foil Nucleus
Ernest Rutherford
Protons - Electrons =
Charge
Atoms that have a negative charge
Anion
Phosphorus
.
. P :
.
84 -5
Kr
36
P = 36
E = 41
N = 48
Father of atom
John Dalton
Mass Number - Protons =
Number of Neutrons
Outermost energy level of an atom
Valence Shell
Iodine
..
: I :
.
210 +43
Fm
100
P = 100
E = 57
N = 110
Plum Pudding Model
JJ Thompson
Protons - Charge =
Number of Electrons