Number Element Name Element Symbol Atomic Number Average Atomic Mass Group Period Electron Configuration Electronegativity Ionization Energy (kJ/mol) Electron Affinity (kJ/mol) Standard State Type Atomic Radius Melting Point Density at STP Year Discovered
1 Hydrogen H 1 1.008 1 1 1s1 2.20 1312 72.8 Gas Nonmetal 25 pm 14.01 K 0.0899 g/cm³ 1766
2 Helium He 2 4.0026 18 1 1s2 – 2372 0 Gas Noble gas 31 pm – 0.1785 g/cm³ 1868
3 Lithium Li 3 6.94 1 2 [He] 2s1 0.98 520 59.6 Solid Alkali metal 145 pm 453.65 K 0.534 g/cm³ 1817
4 Beryllium Be 4 9.0122 2 2 [He] 2s2 1.57 900 0 Solid Alkaline earth metal 105 pm 1560 K 1.85 g/cm³ 1798
4 Beryllium Be 4 9.0122 2 2 [He] 2s2 1.57 900 0 Solid Alkaline earth metal 105 pm 1560 K 1.85 g/cm³ 1798
5 Boron B 5 10.81 13 2 [He] 2s2 2p1 2.04 801 26.7 Solid Metalloid 85 pm 2348 K 2.34 g/cm³ 1808
6 Carbon C 6 12.01 14 2 [He] 2s2 2p2 2.55 1087 121.8 Solid Nonmetal 70 pm 3915 K 2.26 g/cm³ Ancient
7 Nitrogen N 7 14.01 15 2 [He] 2s2 2p3 3.04 1402 7 Gas Nonmetal 65 pm 63.15 K 0.00125 g/cm³ 1772
8 Oxygen O 8 16.00 16 2 [He] 2s2 2p4 3.44 1314 141 Gas Nonmetal 60 pm 54.36 K 0.00143 g/cm³ 1774
9 Fluorine F 9 19.00 17 2 [He] 2s2 2p5 3.98 1681 328 Gas Halogen 50 pm 53.53 K 0.0017 g/cm³ 1670
10 Neon Ne 10 20.18 18 2 [He] 2s2 2p6 – 2081 0 Gas Noble gas 38 pm 24.56 K 0.0009 g/cm³ 1898
11 Sodium Na 11 22.99 1 3 [Ne] 3s1 0.93 496 52.8 Solid Alkali metal 180 pm 370.95 K 0.971 g/cm³ 1807
12 Magnesium Mg 12 24.31 2 3 [Ne] 3s2 1.31 738 0 Solid Alkaline earth metal 150 pm 923 K 1.738 g/cm³ 1808
13 Aluminum Al 13 26.98 13 3 [Ne] 3s2 3p1 1.61 577 42.5 Solid Post-transition metal 125 pm 933.47 K 2.6989 g/cm³ 1825
14 Silicon Si 14 28.09 14 3 [Ne] 3s2 3p2 1.90 787 134 Solid Metalloid 110 pm 1687 K 2.33 g/cm³ 1824
15 Phosphorus P 15 30.97 15 3 [Ne] 3s2 3p3 2.19 1012 72 Solid Nonmetal 100 pm 317.30 K 1.823 g/cm³ 1669
16 Sulfur S 16 32.06 16 3 [Ne] 3s2 3p4 2.58 999 200 Solid Nonmetal 100 pm 388.36 K 2.067 g/cm³ Ancient
17 Chlorine Cl 17 35.45 17 3 [Ne] 3s2 3p5 3.16 1251 349 Gas Halogen 100 pm 171.65 K 0.003214 g/cm³ 1774
18 Argon Ar 18 39.95 18 3 [Ne] 3s2 3p6 – 1521 0 Gas Noble gas 71 pm 83.80 K 0.001784 g/cm³ 1894
19 Potassium K 19 39.10 1 4 [Ar] 4s1 0.82 419 48.4 Solid Alkali metal 220 pm 336.53 K 0.856 g/cm³ 1807
20 Calcium Ca 20 40.08 2 4 [Ar] 4s2 1.00 590 2.37 Solid Alkaline earth metal 180 pm 1115 K 1.54 g/cm³ Ancient
21 Scandium Sc 21 44.96 3 4 [Ar] 3d1 4s2 1.36 633 18 Solid Transition metal 160 pm 1814 K 2.99 g/cm³ 1876
22 Titanium Ti 22 47.87 4 4 [Ar] 3d2 4s2 1.54 659 8.34 Solid Transition metal 140 pm 1941 K 4.54 g/cm³ 1791
23 Vanadium V 23 50.94 5 4 [Ar] 3d3 4s2 1.63 651 50.6 Solid Transition metal 135 pm 2183 K 6.11 g/cm³ 1803
24 Chromium Cr 24 52.00 6 4 [Ar] 3d5 4s1 1.66 653 65 Solid Transition metal 128 pm 2180 K 7.15 g/cm³ 1797
25 Manganese Mn 25 54.94 7 4 [Ar] 3d5 4s2 1.55 717 0 Solid Transition metal 127 pm 1519 K 7.44 g/cm³ 1774
26 Iron Fe 26 55.85 8 4 [Ar] 3d6 4s2 1.83 763 15.7 Solid Transition metal 126 pm 1811 K 7.87 g/cm³ Ancient
27 Cobalt Co 27 58.93 9 4 [Ar] 3d7 4s2 1.88 760 63.7 Solid Transition metal 125 pm 1768 K 8.90 g/cm³ 1735
28 Nickel Ni 28 58.69 10 4 [Ar] 3d8 4s2 1.91 737 111 Solid Transition metal 124 pm 1728 K 8.91 g/cm³ 1751
29 Copper Cu 29 63.55 11 4 [Ar] 3d10 4s1 1.90 746 119 Solid Transition metal 128 pm 1357.77 K 8.96 g/cm³ Ancient
30 Zinc Zn 30 65.38 12 4 [Ar] 3d10 4s2 1.65 906 0 Solid Transition metal 134 pm 692.88 K 7.13 g/cm³ 1746
31 Gallium Ga 31 69.72 13 4 [Ar] 3d10 4s2 4p1 1.81 579 28.9 Solid Post-transition metal 135 pm 302.91 K 5.91 g/cm³ 1875
32 Germanium Ge 32 72.63 14 4 [Ar] 3d10 4s2 4p2 2.01 762 119 Solid Metalloid 125 pm 1211.40 K 5.32 g/cm³ 1886
33 Arsenic As 33 74.92 15 4 [Ar] 3d10 4s2 4p3 2.18 944 78 Solid Metalloid 115 pm 1090 K 5.73 g/cm³ Ancient
34 Selenium Se 34 78.97 16 4 [Ar] 3d10 4s2 4p4 2.55 941 195 Solid Nonmetal 115 pm 494 K 4.81 g/cm³ 1817
35 Bromine Br 35 79.90 17 4 [Ar] 3d10 4s2 4p5 2.96 1140 324 Liquid Halogen 115 pm 265.95 K 3.14 g/cm³ 1826
36 Krypton Kr 36 83.80 18 4 [Ar] 3d10 4s2 4p6 – 1350 0 Gas Noble gas 88 pm 115.79 K 0.003733 g/cm³ 1898
37 Rubidium Rb 37 85.47 1 5 [Kr] 5s1 0.82 403 46.9 Solid Alkali metal 235 pm 312.46 K 1.532 g/cm³ 1861
38 Strontium Sr 38 87.62 2 5 [Kr] 5s2 0.95 550 5.03 Solid Alkaline earth metal 200 pm 1050 K 2.63 g/cm³ 1790
39 Yttrium Y 39 88.91 3 5 [Kr] 4d1 5s2 1.22 600 29.6 Solid Transition metal 180 pm 1799 K 4.47 g/cm³ 1794
40 Zirconium Zr 40 91.22 4 5 [Kr] 4d2 5s2 1.33 640 41 Solid Transition metal 160 pm 2128 K 6.51 g/cm³ 1789
41 Niobium Nb 41 92.91 5 5 [Kr] 4d4 5s1 1.60 652 86 Solid Transition metal 146 pm 2750 K 8.57 g/cm³ 1801
42 Molybdenum Mo 42 95.95 6 5 [Kr] 4d5 5s1 2.16 684 72.1 Solid Transition metal 139 pm 2896 K 10.28 g/cm³ 1778
43 Technetium Tc 43 98.00 7 5 [Kr] 4d5 5s2 1.90 702 53 Solid Transition metal 136 pm 2430 K 11.49 g/cm³ 1937
44 Ruthenium Ru 44 101.1 8 5 [Kr] 4d7 5s1 2.20 710 101.3 Solid Transition metal 130 pm 2607 K 12.37 g/cm³ 1844
45 Rhodium Rh 45 102.9 9 5 [Kr] 4d8 5s1 2.28 720 109.7 Solid Transition metal 135 pm 2237 K 12.41 g/cm³ 1803
46 Palladium Pd 46 106.4 10 5 [Kr] 4d10 2.20 804 53.7 Solid Transition metal 131 pm 1828.05 K 12.02 g/cm³ 1803
47 Silver Ag 47 107.9 11 5 [Kr] 4d10 5s1 1.93 731 125.6 Solid Transition metal 153 pm 1234.93 K 10.50 g/cm³ Ancient
48 Cadmium Cd 48 112.4 12 5 [Kr] 4d10 5s2 1.69 868 0 Solid Transition metal 148 pm 594.22 K 8.65 g/cm³ 1817
49 Indium In 49 114.8 13 5 [Kr] 4d10 5s2 5p1 1.78 558 28.9 Solid Post-transition metal 144 pm 429.75 K 7.31 g/cm³ 1863
50 Tin Sn 50 118.7 14 5 [Kr] 4d10 5s2 5p2 1.96 709 114 Solid Post-transition metal 141 pm 505.08 K 7.29 g/cm³ Ancient
51 Antimony Sb 51 121.8 15 5 [Kr] 4d10 5s2 5p3 2.05 834 103 Solid Metalloid 138 pm 903.78 K 6.68 g/cm³ Ancient
52 Tellurium Te 52 127.6 16 5 [Kr] 4d10 5s2 5p4 2.1 869 190 Solid Metalloid 135 pm 722.66 K 6.24 g/cm³ 1782
53 Iodine I 53 126.9 17 5 [Kr] 4d10 5s2 5p5 2.66 1008 295 Solid Halogen 133 pm 386.85 K 4.93 g/cm³ 1811
54 Xenon Xe 54 131.3 18 5 [Kr] 4d10 5s2 5p6 2.6 1170 0 Gas Noble gas 130 pm 161.36 K 0.005887 g/cm³ 1898
55 Cesium Cs 55 132.9 1 6 [Xe] 6s1 0.79 376 45.5 Solid Alkali metal 235 pm 301.59 K 1.93 g/cm³ 1860
56 Barium Ba 56 137.3 2 6 [Xe] 6s2 0.89 502 13.95 Solid Alkaline earth metal 198 pm 1000 K 3.51 g/cm³ 1808
57 Lanthanum La 57 138.9 – 6 [Xe] 5d1 6s2 1.1 538 53 Solid Lanthanide 169 pm 1193 K 6.15 g/cm³ 1839
58 Cerium Ce 58 140.1 – 6 [Xe] 4f1 5d1 6s2 1.12 534 50 Solid Lanthanide 215 pm 1068 K 6.77 g/cm³ 1803
59 Praseodymium Pr 59 140.9 – 6 [Xe] 4f3 6s2 1.13 527 50 Solid Lanthanide 247 pm 1208 K 6.77 g/cm³ 1885
60 Neodymium Nd 60 144.2 – 6 [Xe] 4f4 6s2 1.14 533 50 Solid Lanthanide 206 pm 1297 K 7.01 g/cm³ 1885
61 Promethium Pm 61 145 – 6 [Xe] 4f5 6s2 – 540 0 Solid Lanthanide 205 pm 1315 K 7.26 g/cm³ 1945
62 Samarium Sm 62 150.4 – 6 [Xe] 4f6 6s2 1.17 544 50 Solid Lanthanide 238 pm 1347 K 7.52 g/cm³ 1879
63 Europium Eu 63 152.0 – 6 [Xe] 4f7 6s2 1.2 547 50 Solid Lanthanide 231 pm 1095 K 5.24 g/cm³ 1901
64 Gadolinium Gd 64 157.3 – 6 [Xe] 4f7 5d1 6s2 1.2 593 50 Solid Lanthanide 233 pm 1585 K 7.90 g/cm³ 1880
65 Terbium Tb 65 158.9 – 6 [Xe] 4f9 6s2 1.2 565 50 Solid Lanthanide 225 pm 1629 K 8.23 g/cm³ 1843
66 Dysprosium Dy 66 162.5 – 6 [Xe] 4f10 6s2 1.22 573 50 Solid Lanthanide 228 pm 1680 K 8.54 g/cm³ 1886
67 Holmium Ho 67 164.9 – 6 [Xe] 4f11 6s2 1.23 581 50 Solid Lanthanide 226 pm 1747 K 8.80 g/cm³ 1878
68 Erbium Er 68 167.3 – 6 [Xe] 4f12 6s2 1.24 589 50 Solid Lanthanide 226 pm 1802 K 9.06 g/cm³ 1842
69 Thulium Tm 69 168.9 – 6 [Xe] 4f13 6s2 1.25 597 50 Solid Lanthanide 222 pm 1818 K 9.32 g/cm³ 1879
70 Ytterbium Yb 70 173.1 – 6 [Xe] 4f14 6s2 1.1 603 50 Solid Lanthanide 222 pm 1092 K 6.90 g/cm³ 1878
71 Lutetium Lu 71 175.0 – 6 [Xe] 4f14 5d1 6s2 1.27 523 217 Solid Lanthanide 217 pm 1925 K 9.84 g/cm³ 1907
72 Hafnium Hf 72 178.5 4 6 [Xe] 4f14 5d2 6s2 1.3 659 0 Solid Transition metal 208 pm 2506 K 13.31 g/cm³ 1923
73 Tantalum Ta 73 180.9 5 6 [Xe] 4f14 5d3 6s2 1.5 761 31 Solid Transition metal 200 pm 3290 K 16.65 g/cm³ 1802
74 Tungsten W 74 183.8 6 6 [Xe] 4f14 5d4 6s2 2.36 770 78.6 Solid Transition metal 193 pm 3695 K 19.25 g/cm³ 1783
75 Rhenium Re 75 186.2 7 6 [Xe] 4f14 5d5 6s2 1.9 760 14.5 Solid Transition metal 188 pm 3459 K 21.02 g/cm³ 1925
76 Osmium Os 76 190.2 8 6 [Xe] 4f14 5d6 6s2 2.2 840 106.1 Solid Transition metal 185 pm 3306 K 22.59 g/cm³ 1803
77 Iridium Ir 77 192.2 9 6 [Xe] 4f14 5d7 6s2 2.2 880 150.9 Solid Transition metal 180 pm 2719 K 22.56 g/cm³ 1803
78 Platinum Pt 78 195.1 10 6 [Xe] 4f14 5d9 6s1 2.28 870 205.3 Solid Transition metal 177 pm 2041 K 21.45 g/cm³ 1735
79 Gold Au 79 196.9 11 6 [Xe] 4f14 5d10 6s1 2.54 890 222.8 Solid Transition metal 174 pm 1337.33 K 19.32 g/cm³ Ancient
80 Mercury Hg 80 200.6 12 6 [Xe] 4f14 5d10 6s2 2.0 1007 0 Liquid Transition metal 171 pm 234.32 K 13.53 g/cm³ Ancient
81 Thallium Tl 81 204.4 13 6 [Xe] 4f14 5d10 6s2 6p1 2.04 589 19.2 Solid Post-transition metal 156 pm 577 K 11.85 g/cm³ 1861
82 Lead Pb 82 207.2 14 6 [Xe] 4f14 5d10 6s2 6p2 2.33 715 35.1 Solid Post-transition metal 154 pm 600.61 K 11.34 g/cm³ Ancient
83 Bismuth Bi 83 208.9 15 6 [Xe] 4f14 5d10 6s2 6p3 2.02 703 90.0 Solid Post-transition metal 143 pm 544.55 K 9.78 g/cm³ Ancient
84 Polonium Po 84 209 16 6 [Xe] 4f14 5d10 6s2 6p4 2.0 812 183.3 Solid Metalloid 135 pm 527 K 9.20 g/cm³ 1898
85 Astatine At 85 210 17 6 [Xe] 4f14 5d10 6s2 6p5 2.2 920 270 Solid Halogen 127 pm 575 K 7 g/cm³ 1940
86 Radon Rn 86 222 18 6 [Xe] 4f14 5d10 6s2 6p6 – 1037 0 Gas Noble gas 120 pm 202 K 0.00973 g/cm³ 1900
87 Francium Fr 87 223 1 7 [Rn] 7s1 – 393 0 Solid Alkali metal – 300 K 1.87 g/cm³ 1939
88 Radium Ra 88 226 2 7 [Rn] 7s2 – 700 0 Solid Alkaline earth metal – 973 K 5.5 g/cm³ 1898
89 Actinium Ac 89 227 – 7 [Rn] 6d1 7s2 1.1 1050 0 Solid Actinide – 1324 K 10.07 g/cm³ 1899
90 Thorium Th 90 232 – 7 [Rn] 6d2 7s2 1.3 1115 54.4 Solid Actinide 179 pm 2023 K 11.72 g/cm³ 1828
91 Protactinium Pa 91 231 – 7 [Rn] 5f2 6d1 7s2 1.5 1840 0 Solid Actinide – 1845 K 15.37 g/cm³ 1913
92 Uranium U 92 238.0 – 7 [Rn] 5f3 6d1 7s2 1.38 1405 19.05 Solid Actinide 186 pm 1408 K 19.05 g/cm³ 1789
93 Neptunium Np 93 237 – 7 [Rn] 5f4 6d1 7s2 1.36 912 0 Solid Actinide – 912 K 20.25 g/cm³ 1940
94 Plutonium Pu 94 244 – 7 [Rn] 5f6 7s2 1.28 913 0 Solid Actinide 175 pm 912.5 K 19.84 g/cm³ 1940
95 Americium Am 95 243 – 7 [Rn] 5f7 7s2 1.3 1449 0 Solid Actinide – 1449 K 13.67 g/cm³ 1944
96 Curium Cm 96 247 – 7 [Rn] 5f7 6d1 7s2 1.3 1613 0 Solid Actinide – 1613 K 13.51 g/cm³ 1944
97 Berkelium Bk 97 247 – 7 [Rn] 5f9 7s2 1.3 – 0 Solid Actinide – 1259 K 14.78 g/cm³ 1949
98 Californium Cf 98 251 – 7 [Rn] 5f10 7s2 1.3 – 0 Solid Actinide – 1173 K 15.1 g/cm³ 1950
99 Einsteinium Es 99 252 – 7 [Rn] 5f11 7s2 1.3 – 0 Solid Actinide – 1133 K – 1952
100 Fermium Fm 100 257 – 7 [Rn] 5f12 7s2 1.3 – 0 Solid Actinide – – – 1952
101 Mendelevium Md 101 258 – 7 [Rn] 5f13 7s2 1.3 – 0 Solid Actinide – – – 1955
102 Nobelium No 102 259 – 7 [Rn] 5f14 7s2 1.3 – 0 Solid Actinide – – – 1958
103 Lawrencium Lr 103 262 – 7 [Rn] 5f14 6d1 7s2 1.3 – 0 Solid Actinide – – – 1961
104 Rutherfordium Rf 104 267 4 7 [Rn] 5f14 6d2 7s2 – 580 0 Solid Transition metal – 2400 K 23.2 g/cm³ 1969
105 Dubnium Db 105 270 5 7 [Rn] 5f14 6d3 7s2 – – 0 Solid Transition metal – – – 1967
106 Seaborgium Sg 106 271 6 7 [Rn] 5f14 6d4 7s2 – – 0 Solid Transition metal – – – 1974
107 Bohrium Bh 107 270 7 7 [Rn] 5f14 6d5 7s2 – – 0 Solid Transition metal – – – 1981
108 Hassium Hs 108 277 8 7 [Rn] 5f14 6d6 7s2 – – 0 Solid Transition metal – – – 1984
109 Meitnerium Mt 109 278 9 7 [Rn] 5f14 6d7 7s2 – – 0 Solid Unknown – – – 1982
110 Darmstadtium Ds 110 281 10 7 [Rn] 5f14 6d9 7s1 – – 0 Solid Unknown – – – 1994
111 Roentgenium Rg 111 282 11 7 [Rn] 5f14 6d10 7s1 – – 0 Solid Unknown – – – 1994
112 Copernicium Cn 112 285 12 7 [Rn] 5f14 6d10 7s2 – – 0 Solid Transition metal – – – 1996
113 Nihonium Nh 113 286 13 7 [Rn] 5f14 6d10 7s2 7p1 – – 0 Solid Unknown – – – 2003
114 Flerovium Fl 114 289 14 7 [Rn] 5f14 6d10 7s2 7p2 – – 0 Solid Unknown – – – 1998
115 Moscovium Mc 115 290 15 7 [Rn] 5f14 6d10 7s2 7p3 – – 0 Solid Unknown – – – 2003
116 Livermorium Lv 116 293 16 7 [Rn] 5f14 6d10 7s2 7p4 – – 0 Solid Unknown – – – 2000
117 Tennessine Ts 117 294 17 7 [Rn] 5f14 6d10 7s2 7p5 – – 0 Solid Unknown – – – 2010
118 Oganesson Og 118 294 18 7 [Rn] 5f14 6d10 7s2 7p6 – – 0 Solid Unknown – – – 2002