<Li> Both Li and Mg form covalent organometallic compounds . LiMe and MgMe (cf . Grignard reagents) are both valuable synthetic reagents . The other Group 1 and Group 2 analogues are ionic and extremely reactive (and hence difficult to manipulate). </Li> <Li> Chlorides of both Li and Mg are deliquescent (absorb moisture from surroundings) and soluble in alcohol and pyridine . Lithium chloride, like magnesium chloride (MgCl. 6H O) separates out from hydrated crystal LiCl. 2H O . </Li>

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