Z Element No. of electrons / shell Group Hydrogen Helium 18 Lithium 2, 1 Beryllium 2, 2 5 Boron 2, 3 13 6 Carbon 2, 4 14 7 Nitrogen 2, 5 15 8 Oxygen 2, 6 16 9 Fluorine 2, 7 17 10 Neon 2, 8 18 11 Sodium 2, 8, 1 12 Magnesium 2, 8, 2 13 Aluminium 2, 8, 3 13 14 Silicon 2, 8, 4 14 15 Phosphorus 2, 8, 5 15 16 Sulfur 2, 8, 6 16 17 Chlorine 2, 8, 7 17 18 Argon 2, 8, 8 18 19 Potassium 2, 8, 8, 1 20 Calcium 2, 8, 8, 2 21 Scandium 2, 8, 9, 2 22 Titanium 2, 8, 10, 2 23 Vanadium 2, 8, 11, 2 5 24 Chromium 2, 8, 13, 1 6 25 Manganese 2, 8, 13, 2 7 26 Iron 2, 8, 14, 2 8 27 Cobalt 2, 8, 15, 2 9 28 Nickel 2, 8, 16, 2 10 29 Copper 2, 8, 18, 1 11 30 Zinc 2, 8, 18, 2 12 31 Gallium 2, 8, 18, 3 13 32 Germanium 2, 8, 18, 4 14 33 Arsenic 2, 8, 18, 5 15 34 Selenium 2, 8, 18, 6 16 35 Bromine 2, 8, 18, 7 17 36 Krypton 2, 8, 18, 8 18 37 Rubidium 2, 8, 18, 8, 1 38 Strontium 2, 8, 18, 8, 2 39 Yttrium 2, 8, 18, 9, 2 40 Zirconium 2, 8, 18, 10, 2 41 Niobium 2, 8, 18, 12, 1 5 42 Molybdenum 2, 8, 18, 13, 1 6 43 Technetium 2, 8, 18, 13, 2 7 44 Ruthenium 2, 8, 18, 15, 1 8 45 Rhodium 2, 8, 18, 16, 1 9 46 Palladium 2, 8, 18, 18 10 47 Silver 2, 8, 18, 18, 1 11 48 Cadmium 2, 8, 18, 18, 2 12 49 Indium 2, 8, 18, 18, 3 13 50 Tin 2, 8, 18, 18, 4 14 51 Antimony 2, 8, 18, 18, 5 15 52 Tellurium 2, 8, 18, 18, 6 16 53 Iodine 2, 8, 18, 18, 7 17 54 Xenon 2, 8, 18, 18, 8 18 55 Caesium 2, 8, 18, 18, 8, 1 56 Barium 2, 8, 18, 18, 8, 2 57 Lanthanum 2, 8, 18, 18, 9, 2 58 Cerium 2, 8, 18, 19, 9, 2 59 Praseodymium 2, 8, 18, 21, 8, 2 60 Neodymium 2, 8, 18, 22, 8, 2 61 Promethium 2, 8, 18, 23, 8, 2 62 Samarium 2, 8, 18, 24, 8, 2 63 Europium 2, 8, 18, 25, 8, 2 64 Gadolinium 2, 8, 18, 25, 9, 2 65 Terbium 2, 8, 18, 27, 8, 2 66 Dysprosium 2, 8, 18, 28, 8, 2 67 Holmium 2, 8, 18, 29, 8, 2 68 Erbium 2, 8, 18, 30, 8, 2 69 Thulium 2, 8, 18, 31, 8, 2 70 Ytterbium 2, 8, 18, 32, 8, 2 71 Lutetium 2, 8, 18, 32, 9, 2 72 Hafnium 2, 8, 18, 32, 10, 2 73 Tantalum 2, 8, 18, 32, 11, 2 5 74 Tungsten 2, 8, 18, 32, 12, 2 6 75 Rhenium 2, 8, 18, 32, 13, 2 7 76 Osmium 2, 8, 18, 32, 14, 2 8 77 Iridium 2, 8, 18, 32, 15, 2 9 78 Platinum 2, 8, 18, 32, 17, 1 10 79 Gold 2, 8, 18, 32, 18, 1 11 80 Mercury 2, 8, 18, 32, 18, 2 12 81 Thallium 2, 8, 18, 32, 18, 3 13 82 Lead 2, 8, 18, 32, 18, 4 14 83 Bismuth 2, 8, 18, 32, 18, 5 15 84 Polonium 2, 8, 18, 32, 18, 6 16 85 Astatine 2, 8, 18, 32, 18, 7 17 86 Radon 2, 8, 18, 32, 18, 8 18 87 Francium 2, 8, 18, 32, 18, 8, 1 88 Radium 2, 8, 18, 32, 18, 8, 2 89 Actinium 2, 8, 18, 32, 18, 9, 2 90 Thorium 2, 8, 18, 32, 18, 10, 2 91 Protactinium 2, 8, 18, 32, 20, 9, 2 92 Uranium 2, 8, 18, 32, 21, 9, 2 93 Neptunium 2, 8, 18, 32, 22, 9, 2 94 Plutonium 2, 8, 18, 32, 24, 8, 2 95 Americium 2, 8, 18, 32, 25, 8, 2 96 Curium 2, 8, 18, 32, 25, 9, 2 97 Berkelium 2, 8, 18, 32, 27, 8, 2 98 Californium 2, 8, 18, 32, 28, 8, 2 99 Einsteinium 2, 8, 18, 32, 29, 8, 2 100 Fermium 2, 8, 18, 32, 30, 8, 2 101 Mendelevium 2, 8, 18, 32, 31, 8, 2 102 Nobelium 2, 8, 18, 32, 32, 8, 2 103 Lawrencium 2, 8, 18, 32, 32, 8, 3 104 Rutherfordium 2, 8, 18, 32, 32, 10, 2 105 Dubnium 2, 8, 18, 32, 32, 11, 2 5 106 Seaborgium 2, 8, 18, 32, 32, 12, 2 6 107 Bohrium 2, 8, 18, 32, 32, 13, 2 7 108 Hassium 2, 8, 18, 32, 32, 14, 2 8 109 Meitnerium 2, 8, 18, 32, 32, 15, 2 (?) 9 110 Darmstadtium 2, 8, 18, 32, 32, 16, 2 (?) 10 111 Roentgenium 2, 8, 18, 32, 32, 17, 2 (?) 11 112 Copernicium 2, 8, 18, 32, 32, 18, 2 (?) 12 113 Nihonium 2, 8, 18, 32, 32, 18, 3 (?) 13 114 Flerovium 2, 8, 18, 32, 32, 18, 4 (?) 14 115 Moscovium 2, 8, 18, 32, 32, 18, 5 (?) 15 116 Livermorium 2, 8, 18, 32, 32, 18, 6 (?) 16 117 Tennessine 2, 8, 18, 32, 32, 18, 7 (?) 17 118 Oganesson 2, 8, 18, 32, 32, 18, 8 (?) 18
how many electrons are there in the second principal energy level of a phosphorus atom
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