Typically, a molecular formula begins with the nonmetal that is closest to the lower left corner of the periodic table, except that hydrogen is almost never written first (H2O is the prominent exception). Instead, it tells you, if they were to form a bond, what kind of bond they would have. The electronegativity of an atom depends upon its atomic number and its atomic radius, which means that the more the distance between the nucleus and its valence electrons, the lower the electronegativity and vice versa. Sodium metal has a positive charge, and chlorine gas has a negative charge on it, which causes these ions to form an ionic bond. [CDATA[*/{"annotations":null,"assetRoot":"chrome-extension://bjfhmglciegochdpefhhlphglcehbmek/client/","branding":null,"clientUrl":"chrome-extension://bjfhmglciegochdpefhhlphglcehbmek/client/build/boot.js","oauthEnabled":null,"onLayoutChange":null,"openLoginForm":null,"openSidebar":null,"query":null,"services":null,"showHighlights":"always","sidebarAppUrl":"chrome-extension://bjfhmglciegochdpefhhlphglcehbmek/client/app.html","subFrameIdentifier":"08977406609586949","pluginClasses":{}}/*]]>*/, /**/, /*c__DisplayClass228_0.
