Similarities between Lithium and Magnesium || Points of Similarities between Lithium and Magnesium ||

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The similarity between lithium and magnesium is particularly striking and arises because of their similar size: atomic radii, L i = 152 pm, Mg = 160 pm; ionic radii : L i+ = 76 pm, Mg 2+ = 72 pm. 

The main points of similarity are : 

» Both lithium and magnesium are harder and lighter than other elements in the respective groups.

» Lithium and magnesium react slowly with water. Their oxides and hydroxides are much lesser soluble and their hydroxides decomposes on heating. Both forms a nitride, Li3 N and Mg3 N2, by direct combination with nitrogen(N2) . 

» The oxides, Li2 O and Mg O do not combine with excess oxygen to give any superoxide.

» The carbonates of lithium and magnesium decompose easily on heating to form the oxides and C O2 . Solid hydrogen carbonates are not formed from lithium and magnesium.  

»Both L i Cl and Mg Cl2 are soluble in ethanol. 

» Both L i Cl and Mg Cl2  are deliquescent and crystallise from aqueous solution as hydrates, L i Cl.2H2O and Mg Cl2 . 6H2O.

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