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Covalent Radius of the Elements

Caesium has the largest covalent radius (244 pm) and hydrogen the smallest (31 pm).

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1 H 31 2 He —3 Li 128 4 Be 96 5 B 84 6 C 76 7 N 71 8 O 66 9 F 57 10 Ne —11 Na 166 12 Mg 141 13 Al 121 14 Si 111 15 P 107 16 S 105 17 Cl 102 18 Ar 106 19 K 203 20 Ca 176 21 Sc 170 22 Ti 160 23 V 153 24 Cr 139 25 Mn 139 26 Fe 132 27 Co 126 28 Ni 124 29 Cu 132 30 Zn 122 31 Ga 122 32 Ge 120 33 As 119 34 Se 120 35 Br 120 36 Kr 116 37 Rb 220 38 Sr 195 39 Y 190 40 Zr 175 41 Nb 164 42 Mo 154 43 Tc 147 44 Ru 146 45 Rh 142 46 Pd 139 47 Ag 145 48 Cd 144 49 In 142 50 Sn 139 51 Sb 139 52 Te 138 53 I 139 54 Xe 140 55 Cs 244 56 Ba 215 57 La 207 58 Ce 204 59 Pr 203 60 Nd 201 61 Pm —62 Sm 198 63 Eu 198 64 Gd 196 65 Tb 194 66 Dy 192 67 Ho 192 68 Er 189 69 Tm 190 70 Yb 187 71 Lu 187 72 Hf 175 73 Ta 170 74 W 162 75 Re 151 76 Os 144 77 Ir 141 78 Pt 136 79 Au 136 80 Hg 132 81 Tl 145 82 Pb 146 83 Bi 148 84 Po 140 85 At —86 Rn —87 Fr —88 Ra 221 89 Ac —90 Th 206 91 Pa —92 U 196 93 Np 190 94 Pu 187 95 Am 180 96 Cm 169 97 Bk —98 Cf —99 Es —100 Fm —101 Md —102 No —103 Lr —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 —

1 H,Hydrogen

Nonmetals · Gas

Covalent radius 31pm

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All elements by covalent radius

Half the length of a single covalent bond between two atoms of the element. It shows the size of an atom inside a molecule or crystal: 76 pm for carbon, 132 pm for iron.

Source: Cordero et al. (2008)

1 Caesium 244pm
2 Radium 221pm
3 Rubidium 220pm
4 Barium 215pm
5 Lanthanum 207pm
6 Thorium 206pm
7 Cerium 204pm
8 Potassium 203pm
9 Praseodymium 203pm
10 Neodymium 201pm
11 Samarium 198pm
12 Europium 198pm
13 Gadolinium 196pm
14 Uranium 196pm
15 Strontium 195pm
16 Terbium 194pm
17 Dysprosium 192pm
18 Holmium 192pm
19 Yttrium 190pm
20 Thulium 190pm
21 Neptunium 190pm
22 Erbium 189pm
23 Ytterbium 187pm
24 Lutetium 187pm
25 Plutonium 187pm
26 Americium 180pm
27 Calcium 176pm
28 Zirconium 175pm
29 Hafnium 175pm
30 Scandium 170pm
31 Tantalum 170pm
32 Curium 169pm
33 Sodium 166pm
34 Niobium 164pm
35 Tungsten 162pm
36 Titanium 160pm
37 Molybdenum 154pm
38 Vanadium 153pm
39 Rhenium 151pm
40 Bismuth 148pm
41 Technetium 147pm
42 Ruthenium 146pm
43 Lead 146pm
44 Silver 145pm
45 Thallium 145pm
46 Cadmium 144pm
47 Osmium 144pm
48 Rhodium 142pm
49 Indium 142pm
50 Magnesium 141pm
51 Iridium 141pm
52 Xenon 140pm
53 Polonium 140pm
54 Chromium 139pm
55 Manganese 139pm
56 Palladium 139pm
57 Tin 139pm
58 Antimony 139pm
59 Iodine 139pm
60 Tellurium 138pm
61 Platinum 136pm
62 Gold 136pm
63 Iron 132pm
64 Copper 132pm
65 Mercury 132pm
66 Lithium 128pm
67 Cobalt 126pm
68 Nickel 124pm
69 Zinc 122pm
70 Gallium 122pm
71 Aluminium 121pm
72 Germanium 120pm
73 Selenium 120pm
74 Bromine 120pm
75 Arsenic 119pm
76 Krypton 116pm
77 Silicon 111pm
78 Phosphorus 107pm
79 Argon 106pm
80 Sulfur 105pm
81 Chlorine 102pm
82 Beryllium 96pm
83 Boron 84pm
84 Carbon 76pm
85 Nitrogen 71pm
86 Oxygen 66pm
87 Fluorine 57pm
88 Hydrogen 31pm

No data

Helium (He), Neon (Ne), Promethium (Pm), Astatine (At), Radon (Rn), Francium (Fr), Actinium (Ac), Protactinium (Pa), Berkelium (Bk), Californium (Cf), Einsteinium (Es), Fermium (Fm), Mendelevium (Md), Nobelium (No), Lawrencium (Lr), Rutherfordium (Rf), Dubnium (Db), Seaborgium (Sg), Bohrium (Bh), Hassium (Hs), Meitnerium (Mt), Darmstadtium (Ds), Roentgenium (Rg), Copernicium (Cn), Nihonium (Nh), Flerovium (Fl), Moscovium (Mc), Livermorium (Lv), Tennessine (Ts), Oganesson (Og)