What is an Atomic Number?

What is an Atomic Number?

Site IndexSitemapAtomsProtonsNeutrons
ElectronsPeriodic LawAtomic Number? - What's That?

What is an Atomic Number?
Each Chemical element on the Periodic table is given a unique Atomic Number - a Periodic Table Number. Atoms are made up of three kinds of smaller particles, called protons, neutrons and electrons.

The atomic number is the number of protons in the atom, see Number of Protons and Neutrons. Atoms must have equal numbers of protons and electrons. The chemical elements of the periodic table are listed in order of atomic number

 

What is an Atomic Number? What are Protons and Electrons?
Protons and electrons have different properties. Electrons are tiny, very light particles that have a negative electrical charge. Protons are much larger and heavier than electrons and have a positive charge.

What is an Atomic Number?
In 1913 the English scientist, Henry Moseley, determined the atomic number of each of the elements and modified the 'Periodic Law' accordingly. The atomic number of an element is the same as the number of electrons or protons in that particular atom. Across the Periodic table the elements are placed in the order of their atomic numbers starting with the lowest number of 1 which is the atomic number for hydrogen.

What is an Atomic Number? The Periodic Law
The Periodic Law states that the Physical and Chemical Properties of the elements recur periodically in a systematic and predictable way when the elements are arranged in order of increasing atomic number. The Periodic Table is therefore arranged in order of increasing atomic numbers according to the Periodic Law. The Periodic Law can be explained further by comparing the chemical and physical properties of elements.

What is an Atomic Number? Periodic Trends
When elements in the Periodic Table are arranged according to atomic number, elements show repeating, or periodic trends in their chemical and physical properties.
The Periodic Table can therefore be used by chemists to observe chemical and physical properties, characteristics, patterns and relationships between over 100 elements in just one chart. So the Atomic Number of an element is very important. The higher the atomic number, the greater the number of protons in the nucleus. This means that more neutrons are required to "bind" the nucleus of the atom together.

What is an Atomic Number? Every number is unique...
Every element has a unique Element Symbol and a unique Atomic Number. The same Atomic Number for each element is used all over the world and instantly recognised by scientists and chemists. It is imperative for chemistry students to be able to recognise the names of elements from their Atomic number.

What is an Atomic Number? Atomic Number Chart
The following chart, or list, details the names of all of the Periodic Table elements and their corresponding Atomic Number.

List of Elements and their Atomic Number

Alphabetical List
Atomic Number

 

Numerical List
Atomic Number

Actinium
Aluminium
Americium
Antimony
Argon
Arsenic
Astatine
Barium
Berkelium 
Beryllium
Bismuth
Bohrium
Boron
Bromine
Cadmium
Cesium
Calcium
Californium
Carbon
Cerium
Chlorine
Chromium
Cobalt
Copper
Curium 
Darmstadtium
Dubnium
Dysprosium
Einsteinium 
Erbium
Europium
Fermium
Fluorine
Francium
Gadolinium
Gallium
Germanium
Gold
Hafnium
Hassium
Helium
Holmium
Hydrogen
Indium
Iodine
Iridium
Iron
Krypton
Lanthanum
Lawrencium
Lead
Lithium
Lutetium 
Magnesium
Manganese
Meitnerium
Mendelevium
Mercury
Molybdenum
Neodymium
Neon
Neptunium
Nickel 
Niobium
Nitrogen
Nobelium
Osmium
Oxygen 
Palladium
Phosphorus
Platinum
Plutonium
Polonium
Potassium 
Praseodymium
Promethium
Protactinium 
Radium 
Radon
Rhenium
Rhodium
Roentgenium
Rubidium 
Ruthenium
Rutherfordium
Samarium 
Scandium
Seaborgium 
Selenium
Silicon 
Silver
Sodium 
Strontium
Sulfur
Tantalum
Technetium
Tellurium
Terbium
Thallium
Thorium
Thulium
Tin
Titanium
Tungsten
Ununbium
Ununhexium
Ununoctium
Ununpentium
Ununquadium 
Ununseptium
Ununtrium
Uranium
Vanadium
Xenon 
Ytterbium
Yttrium
Zinc
Zirconium

Ac
Al
Am
Sb
Ar
As
At
Ba
Bk
Be
Bi
Bh
B
Br
Cd
Cs
Ca
Cf
C
Ce
Cl
Cr
Co
Cu
Cm
Ds
Db
Dy
Es
Er
Eu
Fm
F
Fr
Gd
Ga
Ge
Au
Hf
Hs
He
Ho
H
In
I
Ir
Fe
Kr
La
Lr
Pb
Li
Lu
Mg
Mn
Mt
Md
Hg
Mo
Nd
Ne
Np
Ni
Nb
N
No
Os
O
Pd 
P
Pt
Pu
Po
K
Pr
Pm
Pa
Ra
Rn
Re
Rh
Rg
Rb
Ru
Rf
Sm
Sc
Sg
Se
Si
Ag
Na
Sr
S
Ta
Tc
Te
Tb
Tl
Th
Tm
Sn
Ti
W
Uub
Uuh
Uuo
Uup
Uuq
Uus
Uut
U
V
Xe
Yb
Y
Zn
Zr
89
13
95
51
18
33
85
56
97
4
83
107
5
35
48
55
20
98 
6
58
17
24
27
29
96
110
105
66
99
68
63
100
9
87
64
31
32
79
72
108
2
67
1
49
53
77 
26
36 
57
103
82
3
71
12
25
109
101
80
42
60
10
93
28
41
7
102
76
8
46
15
78
94
84
19 
59
61
91
88
86
75
45
111
37
44
104
62
21
106 
34
14
47
11
38
16
73
43
52
65
81
90
69
50
22
74
112
116
118
115
114
117
113
92
23
54
70
39
30 
40
 1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
Hydrogen
Helium
Lithium
Beryllium
Boron
Carbon
Nitrogen
Oxygen
Fluorine
Neon
Sodium
Magnesium
Aluminium
Silicon
Phosphorus
Sulfur
Chlorine
Argon
Potassium
Calcium
Scandium
Titanium
Vanadium
Chromium
Manganese
Iron
Cobalt
Nickel
Copper
Zinc
Gallium
Germanium
Arsenic
Selenium
Bromine
Krypton
Rubidium
Strontium
Yttrium
Zirconium
Niobium
Molybdenum
Technetium
Ruthenium
Rhodium
Palladium
Silver
Cadmium
Indium
Tin
Antimony
Tellurium
Iodine
Xenon
Caesium
Barium
Lanthanum
Cerium
Praseodymium
Neodymium
Promethium
Samarium
Europium
Gadolinium
Terbium
Dysprosium
Holmium
Erbium
Thulium
Ytterbium
Lutetium
Hafnium
Tantalum
Tungsten
Rhenium
Osmium
Iridium
Platinum
Gold
Mercury
Thallium
Lead
Bismuth
Polonium
Astatine
Radon
Francium
Radium
Actinium
Thorium
Protactinium
Uranium
Neptunium
Plutonium
Americium
Curium
Berkelium
Californium
Einsteinium
Fermium
Mendelevium
Nobelium
Lawrencium
Rutherfordium
Dubnium
Seaborgium
Bohrium
Hassium
Meitnerium
Darmstadtium
Roentgenium
Ununbium
Ununtrium
Ununquadium
Ununpentium
Ununhexium
Ununseptium
Ununoctium

List of Elements and their Atomic Number

 

What is an Atomic Number?

  • Homework help to learn the Periodic Table
  • Useful facts and info for all chemistry students
  • Atomic Number of each of the elements
  • History of the Atomic Number
  • Who invented the Atomic Number system?
  • Atomic number of elements
  • The Periodic Table

What is an Atomic Number? - Elements Map!
For additional information about the elements featured on the Periodic Table please refer to our comprehensive Elements Map!

What is an Atomic Number?

What is an Atomic Number on the Periodic Table? The most important chemistry reference there is, and
the cornerstone of science since 1869


 

What is an Atomic Number? - Chart - Names - Chemistry - What is an atomic number - Elements - What is an atomic number - Empty - Chart - Atomic Number - Chart - Chemistry - Chart - Names - Groups - Names - Chart - Atomic Number - What is an atomic number - Names - Chart - Atomic Number - Elements - Names - Chart - Atomic Number - Chart - Atoms - Names - Chart - Atomic Number - Chart - Names - Information - What is an atomic number - Chart - Elements - Info - Table - Period - Chart - Names - Chart - Atomic Number - Names - Information - What is an atomic number - Elements - Info - Chart - Elements - Chemistry - Elements - Information - Elments - Info - What is an atomic number - Periotic - Chart - Table - Chart - Names - Chart - Online - What is an atomic number - Elements - Information - Elements - Names - Chart - Groups - Chart - Chemistry - Chem - Elements - Periotic - Elements - Chart - What is an atomic number - Empty - Elements - Chart - Groups - What is an Atomic Number? - Written By Linda Alchin