Elements

A set of atoms with a specific number of protons.

A one or two-letter 'chemical symbol' is used to represent each element. The first letter is always capitalized. In the cases where a second letter is used, it is never capitalized.

There are three important (and overlapping) classification system for elements that describe attributes of those elements. The periodic table is structured in a way that highlights these classifications/attributes: These important classification are:
  • Metals, Non Metals, Transition Metals and Noble Gasses (discernible by individual elements' background color in the periodic table).
  • Periods (Individual rows of the periodic table.)
  • Groups (Individual columns of the periodic table.)
See the accompanying sections for why these distinctions are important.
Periodic Table (Interactive for Desktop Users)

Periodic Table (Interactive for Desktop Users)

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Periodic Table (Interactive for Desktop Users)
Group 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18
Alkali metals Alkaline earth metals Pnictogen Chalcogens Halogens Noble gases
Period

1

Hydro­gen
1
He­lium
2
2
Lith­ium
3
Beryl­lium
4
Boron
5
Carbon
6
Nitro­gen
7
Oxy­gen
8
Fluor­ine
9
Neon
10
3
So­dium
11
Magne­sium
12
Alumin­ium
13
Sili­con
14
Phos­phorus
15
Sulfur
16
Chlor­ine
17
Argon
18
4
Potas­sium
19
Cal­cium
20
Scan­dium
21
Tita­nium
22
Vana­dium
23
Chrom­ium
24
Manga­nese
25
Iron
26
Cobalt
27
Nickel
28
Copper
29
Zinc
30
Gallium
31
Germa­nium
32
Arsenic
33
Sele­nium
34
Bromine
35
Kryp­ton
36
5
Rubid­ium
37
Stront­ium
38
Yttrium
39
Zirco­nium
40
Nio­bium
41
Molyb­denum
42
Tech­netium
43
Ruthe­nium
44
Rho­dium
45
Pallad­ium
46
Silver
47
Cad­mium
48
Indium
49
Tin
50
Anti­mony
51
Tellur­ium
52
Iodine
53
Xenon
54
6
Cae­sium
55
Barium
56
*
Haf­nium
72
Tanta­lum
73
Tung­sten
74
Rhe­nium
75
Os­mium
76
Iridium
77
Plat­inum
78
Gold
79
Mer­cury
80
Thallium
81
Lead
82
Bis­muth
83
Polo­nium
84
Asta­tine
85
Radon
86
7
Fran­cium
87
Ra­dium
88
**
Ruther­fordium
104
Dub­nium
105
Sea­borgium
106
Bohr­ium
107
Has­sium
108
Meit­nerium
109
Darm­stadtium
110
Roent­genium
111
Coper­nicium
112
Unun­trium
113
Flerov­ium
114
Unun­pentium
115
Liver­morium
116
Unun­septium
117
Unun­octium
118
Lantha­nides
Lan­thanum
57
Cerium
58
Praseo­dymium
59
Neo­dymium
60
Prome­thium
61
Sama­rium
62
Europ­ium
63
Gadolin­ium
64
Ter­bium
65
Dyspro­sium
66
Hol­mium
67
Erbium
68
Thulium
69
Ytter­bium
70
Lute­tium
71
 
** Acti­nides
Actin­ium
89
Thor­ium
90
Protac­tinium
91
Ura­nium
92
Neptu­nium
93
Pluto­nium
94
Ameri­cium
95
Curium
96
Berkel­ium
97
Califor­nium
98
Einstei­nium
99
Fer­mium
100
Mende­levium
101
Nobel­ium
102
Lawren­cium
103
 

black=Solid green=Liquid red=Gas grey=Unknown Color of the atomic number shows state of matter (at STP)
Primordial From decay Synthetic Border shows natural occurrence of the element

Background color shows subcategory in the metal–nonmetal range:
Metal Metalloid Nonmetal Unknown
chemical
properties
Alkali metal Alkaline earth metal Lan­thanide Actinide Transition metal Poor metal Polyatomic nonmetal Diatomic nonmetal Noble gas
Elements ::: characteristics

Isotopes

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Characteristics:
A Variation of a specific element with a specific number of neutrons. Different isotopes of the same element have different atomic weights. For example Carbon with 7 neutrons has an atomic weight of 13 (6 + 7 = 13).

Isotope notation for Carbon with seven neutrons:
Methodology #1:
   carbon-13
Methodology #2:
   13C

Example sentences and simple deduction:

"For example, carbon-12, carbon-13 and carbon-14 are three isotopes of the element carbon with mass numbers 12, 13 and 14 respectively. The atomic number of carbon is 6, which means that every carbon atom has 6 protons, so that the neutron numbers of these isotopes are 6, 7 and 8 respectively." [1]

1. http://en.wikipedia.org/wiki/Isotope
Isotopes ::: characteristics

Neutrons

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Blocks

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s-block

s-block

f-block

f-block

d-block

d-block

p-block

p-block

Groups (Columns of the periodic table)

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Group 6

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Group 7

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Group 8

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Group 5

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Group 1

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Group 4

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Group 3

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Group 2

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Group 9

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Group 10

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Group 16

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Group 17

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Group 18

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Group 15

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Group 14

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Group 11

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Group 12

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Group 13

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Periods (Rows of the periodic table)

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Period 3

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Period 2

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Period 1

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Period 4

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Period 5

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Period 7

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Period 6

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Metals, Non Metals & Metalloids (Colors on the periodic table)

Metals, Non Metals & Metalloids (Colors on the periodic table)

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Metals, Non Metals & Metalloids (Colors on the periodic table)
Image Credit: Wikipedia

Broad and general discussions may break the periodic table into just three classifications as shown:

  • Metals (dark yellow)
  • Non Metals (blue)
  • Metalloids (grayish yellow): The stair-like set of elements closer to the right. These elements are kind of 'in-between'; they are neither metals nor nonmetals.
This is an oversimplification, but it often suffices for discussing - general qualities of each - and their likely role in specific types of chemical bonds. At this level of simplification, noble gases may or may not be separated from nonmetals in order to highlight their full outer shell and unwillingness to form bonds. (The example above, from Wikipedia, does not highlight the noble gasses.) More in detailed discussions often requires more granular classification of elements. Expand the attached sections for further dissection of these broad categories.

Metalloids

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Nonmetals

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Metals

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Elements ::: a subgroup of:

Elements ::: a subgroup of:

Atoms

Atoms

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Atoms
Image Credit: Yzmo

Neutrons

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Protons

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Electrons

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Atoms ::: characteristics

Atomic Weight

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Atomic Number

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Electron Configuration of an Atom

Electron Configuration of an Atom

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Monatomic Ion (aka 'Charged Atom' aka 'Atomic Ion')

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Neutral Atoms (aka Electrically-Neutral Atom)

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Atoms ::: is part of:

Atoms ::: is part of:

Molecule

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Polyatomic Ion (aka Molecular Ion)

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Ionic Compound

Ionic Compound

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Chemistry Primer

Chemistry Primer

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