<http://schema.org/headline>
"Group  1: Hydrogen and the Alkali Metals"^^<http://www.w3.org/2001/XMLSchema#string>
<http://chemwiki.ucdavis.edu/Inorganic_Chemistry/Descriptive_Chemistry/Elements_Organized_by_Block/1_s-Block_Elements/Group__1%3A_The_Alkali_Metals>