| has gloss | eng: << Chemical elements data references Atomic radii Note: All measurements given are in picometers (pm). | class="wikitable" ! number !! symbol !! name ! empirical † ! Calculated ! van der Waals ! covalent ! triple-bondcovalent radii ! metallic radii |- | 1 || H || hydrogen | 35 | 53 | 120 | 38 | no data | |- | 2 || He || helium | no data | 31 | 140 | 32 | no data | |- | 3 || Li || lithium | 145 | 167 | 182 | 134 | no data | 152 |- | 4 || Be || beryllium | 105 | 112 | 153 a | 90 | 85 | 112 |- | 5 || B || boron | 85 | 87 | 192 a | 82 | 73 | |- | 6 || C || carbon | 70 | 67 | 170 | 77 | 60 | |- | 7 || N || nitrogen | 65 | 56 | 155 | 75 | 54 | |- | 8 || O || oxygen | 60 | 48 | 152 | 73 | 53 | |- | 9 || F || fluorine | 50 | 42 | 147 | 71 | 53 | |- | 10 || Ne || neon | no data | 38 | 154 | 69 | no data | |- | 11 || Na || sodium | 180 | 190 | 227 | 154 | no data | 186 |- | 12 || Mg || magnesium | 150 | 145 | 173 | 130 | 127 | 160 |- | 13 || Al || aluminium | 125 | 118 | 184 a | 118 | 111 | 143 |- | 14 || Si || silicon | 110 | 111 | 210 | 111 | 102 | |- | 15 || P || phosphorus | 100 | 98 | 180 | 106 | 94 | |- | 16 || S || sulfur | 100 | 88 | 180 | 102 | 95 | |- | 17 || Cl || chlorine | 100... |