International Union of Pure and Applied Chemistryhttps://iupac.org/wp-content/uploads/2015/07/IUPAC_Periodic_Table-8Jan16.pdf[PDF]IUPAC Periodic Table of the Elements2019年10月15日 · 1 H hydrogen [1.007, 1.009] 1 18 3 Li lithium [6.938, 6.997] 4 Be beryllium 9.012 11 Na sodium 22.99 12 Mg magnesium [24.30, 24.31] 19 K potassium 39.10 20 Ca calcium