Period (periodic table)

A period in the periodic table is any horizontal row of elements.

Each elements in the same period has one more proton than the one to its left. This means its atomic number is one number higher. The elements in the same period are very metallic on the left and nonmetallic on the right. The smaller atoms are on the left and the larger ones are on the right because the atoms have more protons and electrons.

The first period has 2 elements, hydrogen and helium. The second period and third period each have 8 elements. The fourth period and fifth period each have 18 elements. The sixth period and seventh period each have 32 elements. F-block elements are counted in the sixth and seventh periods. Hence, each one has 32 elements in it.

Standard periodic table

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Group →

1

2

3

4

5

6

7

8

9

10

11

12

13

14

15

16

17

18

Period ↓

1

1 H

2 He

2

3 Li

4 Be

5 B

6 C

7 N

8 O

9 F

10 Ne

3

11 Na

12 Mg

13 Al

14 Si

15 P

16 S

17 Cl

18 Ar

4

19 K

20 Ca

21 Sc

22 Ti

23 V

24 Cr

25 Mn

26 Fe

27 Co

28 Ni

29 Cu

30 Zn

31 Ga

32 Ge

33 As

34 Se

35 Br

36 Kr

5

37 Rb

38 Sr

39 Y

40 Zr

41 Nb

42 Mo

43 Tc

44 Ru

45 Rh

46 Pd

47 Ag

48 Cd

49 In

50 Sn

51 Sb

52 Te

53 I

54 Xe

6

55 Cs

56 Ba

* Lanthanides

72 Hf

73 Ta

74 W

75 Re

76 Os

77 Ir

78 Pt

79 Au

80 Hg

81 Tl

82 Pb

83 Bi

84 Po

85 At

86 Rn

7

87  Fr

88 Ra

** Actinides

104 Rf

105 Db

106 Sg

107 Bh

108 Hs

109 Mt

110 Ds

111 Rg

112 Cn

113 Nh

114 Fl

115 Mc

116 Lv

117 Ts

118 Og

8

119  Uue

120  Ubn

*** Superactinides

158 Upo

159 Upe

160 Uhn

161 Uhu

162 Uhb

163 Uht

164 Uhq

165 Uhp

166 Uhh

167 Uhs

168 Uho

169 Uhe

170 Usn

171 Usu

172 Usb

9

173  Ust

174  Usq

**** Eka-superactinides

212 Bub

213 But

214 Buq

215 Bup

216 Buh

217 Bus

10

227  Bbs

228  Bbo

* Lanthanide Series

57 La

58 Ce

59 Pr

60 Nd

61 Pm

62 Sm

63 Eu

64 Gd

65 Tb

66 Dy

67 Ho

68 Er

69 Tm

70 Yb

71 Lu

** Actinide Series

89 Ac

90 Th

91 Pa

92 U

93 Np

94 Pu

95 Am

96 Cm

97 Bk

98 Cf

99 Es

100 Fm

101 Md

102 No

103 Lr

*** Superactinide Series

143 Uqt

144 Uqq

145 Uqp

146 Uqh

147 Uqs

148 Uqo

149 Uqe

150 Upn

151 Upu

152 Upb

153 Upt

154 Upq

155 Upp

156 Uph

157 Ups

*** Superactinide Series

121 Ubu

122 Ubb

123 Ubt

124 Ubq

125 Ubp

126 Ubh

127 Ubs

128 Ubo

129 Ube

130 Utn

131 Utu

132 Utb

133 Utt

134 Utq

135 Utp

136 Uth

137 Uts

138 Uto

139 Ute

140 Uqn

141 Uqu

142 Uqb

Chemical Series of the Periodic Table

• Alkali metals
• Alkaline earths
• Lanthanides
• Actinides
• Superactinides
• Eka-superactinides
• Transition metals
• Poor metals
• Metalloids/Semi metals/Half metals
• Nonmetals
• Halogens
• Noble gases

State at standard temperature and pressure. The color of the number (atomic number) above the element symbol shows the state of the element at normal conditions.

• those in blue are gases
• those in green are liquids
• those in black are solid

 

Group (periodic table)

A group is any column on the periodic table. Elements in the same group usually have similar properties, because they have the same number of electrons in the outermost electron shell. There are eight main groups of elements, numbered 1, 2, and 13-18. The other ten groups are transition metals:

• Group 1: the alkali metals (lithium family) *not including hydrogen
• Group 2: the alkaline earth metals (beryllium family)
• Groups 3-12: the transition metals
• Group 13: the triels (boron family)
• Group 14: the tetrels (carbon family)
• Group 15: the pnictogens (nitrogen family)
• Group 16: the chalcogens (oxygen family)
• Group 17: the halogens (fluorine family)
• Group 18: the noble gases (helium/neon family)
• Alkali Metals
  

  The most reactive metals are Lithium (Li), Sodium (Na), Potassium (K), Rubidium (Rb), Cesium (Cs), and Francium (Fr)

  • never include hydrogen.
  • 
    
  • Transition metals. Transition Metals are the most number of elements in the periodic table. They are Iron (Fe), Copper (Cu), Zinc (Zn), Chromium (Cr), Cobalt (Co), Nickel (Ni), Manganese (Mn), Mercury (Hg), Scandium (Sc), Titanium (Ti), Vanadium (V), Silver (Ag), Gold (Au), Cadmium (Cd), Tungsten (W), Platinum (Pt), Yttrium (Y), Molybdenum (Mo) and others.

  • The noble gases

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    The noble gases are the 18th group in the periodic table. They are Helium (He), Neon (Ne), Argon (Ar), Krypton (Kr), Xenon (Xe), and Radon (Rn). They were previously called Inert gases.

 

Chemical element

A chemical element is a substance that is made up of only one type of atom. Atoms are made up of protons, neutrons, and electrons.

The number of protons in an atom is called the atomic number. For example, all atoms with 6 protons are atoms of the chemical element carbon, and all atoms with 92 protons are atoms of the element uranium. The number of neutrons in the nucleus does not have to be the same in every atom of an element. Atoms of the same element with different numbers of neutrons are called isotopes. Saying that a substance "contains only one type of atom" really means that it contains only atoms that all have the same number of protons.

The number of protons in the nucleus causes its electric charge. This fixes the number of electrons in its normal (un-ionized) state. The electrons in their atomic orbitals determine the element's various chemical properties.

Elements are the basic building blocks for all types of substances. If a substance contains more than one type of atom, it is a compound or a mixture. The smallest particle of a compound is a molecule.

118 different chemical elements are known to modern chemistry. 92 of these elements can be found in nature, and the others can only be made in laboratories. The human body is made up of 26 elements. The last natural element discovered was uranium, in 1789. The first man-made element was technetium, in 1937.

Chemical elements are commonly arranged in the periodic table. Where the elements are in the table tells us about their properties relative to the other elements.

Chemical symbols

Chemical elements are given a unique chemical symbol. Chemical symbols are used all over the world. This means that, no matter which language is spoken, there is no confusion about what the symbol means. Chemical symbols of elements almost always come from their English or Latin names. For example, carbon has the chemical symbol 'C', and sodium has chemical symbol 'Na', after the Latin natrium. Tungsten is called 'W' after its German name, wolfram.  'Au' is the symbol for gold and it comes from the Latin word for gold, aurum. Another symbol which comes from Latin is 'Ag'. This is the element silver and it comes from the Latin argentum. Lead's symbol, 'Pb', comes from the Latin plumbum and the English word plumber derives from this as pipes used to be made out of lead. Some more recently discovered elements were named after famous people, like einsteinium, which was named after Albert Einstein.

Compounds

Elements can join (react) to form pure compounds (such as water, salts, oxides, and organic compounds). In many cases, these compounds have a fixed composition and their own structure and properties. The properties of the compound may be very different from the elements it is made from. Sodium is a metal that burns when put into water and chlorine is a poisonous gas. When they react together they make sodium chloride (salt) which is generally harmless in small quantities and edible.

Mixtures

Some elements mix together in any proportion to form new structures. Such new structures are not compounds. They are called mixtures or, when the elements are metals, alloys.