出典:Wikipedia
出典:『Wikipedia』 (2011/07/08 18:19 UTC 版)
Sodium ( /ˈsoʊdiəm/ soh-dee-əm) is a metallic element with a symbol Na (from Latin natrium or Persian ناترون natrun; perhaps ultimately from Egyptian netjerj), and atomic number 11. It is a soft, silvery-white, highly reactive metal and is a member of the alkali metals within "group 1" (formerly known as 'group IA'). It has one stable isotope, 23Na.