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Chemistry


Electronic configuration of chemical elements

Electrons are arrange around the nucleus of an atom on energy levels (or shells). The maximum number of electrons on an energy level is given by the following formula: 2n2 (n=number of energy level). There are maximum 8 electrons on the outermost energy level. This rule is called Octet rule. Below is the electronic configuration table of all of the known chemical elements.

Chemical element name Atomic number Number of Electrons on each Energy level
1st 2nd 3rd 4th 5th 6th 7th
Hydrogen 1 1 - - - - - -
Helium 2 2 - - - - - -
Lithium 3 2 1 - - - - -
Beryllium 4 2 2 - - - - -
Boron 5 2 3 - - - - -
Carbon 6 2 4 - - - - -
Nitrogen 7 2 5 - - - - -
Oxygen 8 2 6 - - - - -
Fluorine 9 2 7 - - - - -
Neon 10 2 8 - - - - -
Sodium 11 2 8 1 - - - -
Magnesium 12 2 8 2 - - - -
Aluminum 13 2 8 3 - - - -
Silicon 14 2 8 4 - - - -
Phosphorus 15 2 8 5 - - - -
Chemical element name Atomic number Number of Electrons on each Energy level
1st 2nd 3rd 4th 5th 6th 7th
Sulfur 16 2 8 6 - - - -
Chlorine 17 2 8 7 - - - -
Argon 18 2 8 8 - - - -
Potassium 19 2 8 8 1 - - -
Calcium 20 2 8 8 2 - - -
Scandium 21 2 8 9 2 - - -
Titanium 22 2 8 10 2 - - -
Vanadium 23 2 8 11 2 - - -
Chromium 24 2 8 13 1 - - -
Manganese 25 2 8 13 2 - - -
Iron 26 2 8 14 2 - - -
Cobalt 27 2 8 15 2 - - -
Nickel 28 2 8 16 2 - - -
Copper 29 2 8 18 1 - - -
Zinc 30 2 8 18 2 - - -
Chemical element name Atomic number Number of Electrons on each Energy level
1st 2nd 3rd 4th 5th 6th 7th
Gallium 31 2 8 18 3 - - -
Germanium 32 2 8 18 4 - - -
Arsenic 33 2 8 18 5 - - -
Selenium 34 2 8 18 6 - - -
Bromine 35 2 8 18 7 - - -
Krypton 36 2 8 18 8 - - -
Rubidium 37 2 8 18 8 1 - -
Strontium 38 2 8 18 8 2 - -
Yttrium 39 2 8 18 9 2 - -
Zirconium 40 2 8 18 10 2 - -
Niobium 41 2 8 18 12 1 - -
Molybdenum 42 2 8 18 13 1 - -
Technetium 43 2 8 18 14 1 - -
Ruthenium 44 2 8 18 15 1 - -
Rhodium 45 2 8 18 16 1 - -
Chemical element name Atomic number Number of Electrons on each Energy level
1st 2nd 3rd 4th 5th 6th 7th
Palladium 46 2 8 18 18 0 - -
Silver 47 2 8 18 18 1 - -
Cadmium 48 2 8 18 18 2 - -
Indium 49 2 8 18 18 3 - -
Tin 50 2 8 18 18 4 - -
Antimony 51 2 8 18 18 5 - -
Tellurium 52 2 8 18 18 6 - -
Iodine 53 2 8 18 18 7 - -
Xenon 54 2 8 18 18 8 - -
Cesium 55 2 8 18 18 8 1 -
Barium 56 2 8 18 18 8 2 -
Lanthanum 57 2 8 18 18 9 2 -
Cerium 58 2 8 18 20 8 2 -
Praseodymium 59 2 8 18 21 8 2 -
Neodymium 60 2 8 18 22 8 2 -
Chemical element name Atomic number Number of Electrons on each Energy level
1st 2nd 3rd 4th 5th 6th 7th
Promethium 61 2 8 18 23 8 2 -
Samarium 62 2 8 18 24 8 2 -
Europium 63 2 8 18 25 8 2 -
Gadolinium 64 2 8 18 25 9 2 -
Terbium 65 2 8 18 27 8 2 -
Dysprosium 66 2 8 18 28 8 2 -
Holmium 67 2 8 18 29 8 2 -
Erbium 68 2 8 18 30 8 2 -
Thulium 69 2 8 18 31 8 2 -
Ytterbium 70 2 8 18 32 8 2 -
Lutetium 71 2 8 18 32 9 2 -
Hafnium 72 2 8 18 32 10 2 -
Tantalum 73 2 8 18 32 11 2 -
Tungsten 74 2 8 18 32 12 2 -
Rhenium 75 2 8 18 32 13 2 -
Chemical element name Atomic number Number of Electrons on each Energy level
1st 2nd 3rd 4th 5th 6th 7th
Osmium 76 2 8 18 32 14 2 -
Iridium 77 2 8 18 32 15 2 -
Platinum 78 2 8 18 32 17 1 -
Gold 79 2 8 18 32 18 1 -
Mercury 80 2 8 18 32 18 2 -
Thallium 81 2 8 18 32 18 3 -
Lead 82 2 8 18 32 18 4 -
Bismuth 83 2 8 18 32 18 5 -
Polonium 84 2 8 18 32 18 6 -
Astatine 85 2 8 18 32 18 7 -
Radon 86 2 8 18 32 18 8 -
Francium 87 2 8 18 32 18 8 1
Radium 88 2 8 18 32 18 8 2
Actinium 89 2 8 18 32 18 9 2
Thorium 90 2 8 18 32 18 10 2
Chemical element name Atomic number Number of Electrons on each Energy level
1st 2nd 3rd 4th 5th 6th 7th
Protactinium 91 2 8 18 32 20 9 2
Uranium 92 2 8 18 32 21 9 2
Neptunium 93 2 8 18 32 23 8 2
Plutonium 94 2 8 18 32 24 8 2
Americium 95 2 8 18 32 25 8 2
Curium 96 2 8 18 32 25 9 2
Berkelium 97 2 8 18 32 26 9 2
Californium 98 2 8 18 32 28 8 2
Einsteinium 99 2 8 18 32 29 8 2
Fermium 100 2 8 18 32 30 8 2
Mendelevium 101 2 8 18 32 31 8 2
Nobelium 102 2 8 18 32 32 8 2
Lawrencium 103 2 8 18 32 32 9 2
Rutherfordium 104 2 8 18 32 32 10 2
Dubnium 105 2 8 18 32 32 11 2
Chemical element name Atomic number Number of Electrons on each Energy level
1st 2nd 3rd 4th 5th 6th 7th
Seaborgium 106 2 8 18 32 32 12 2
Bohrium 107 2 8 18 32 32 13 2
Hassium 108 2 8 18 32 32 14 2
Meitnerium 109 2 8 18 32 32 15 2
Darmstadtium 110 2 8 18 32 32 16 2
Roentgenium 111 2 8 18 32 32 17 2
Copernicium 112 2 8 18 32 32 18 2
Ununtrium 113 2 8 18 32 32 18 3
Flerovium 114 2 8 18 32 32 18 4
Ununpentium 115 2 8 18 32 32 18 5
Livermorium 116 2 8 18 32 32 18 6
Ununseptium 117 2 8 18 32 32 18 7
Ununoctium 118 2 8 18 32 32 18 8

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