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प्रश्न
Why are lithium salts commonly hydrated and those of the other alkali metal ions usually anhydrous?
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उत्तर
Lithium is the smallest in size among the alkali metals. Hence, Li+ ion can polarize water molecules more easily than other alkali metals. As a result, water molecules get attached to lithium salts as water of crystallization. Hence, lithium salts such as trihydrated lithium chloride (LiCl.3H2O) are commonly hydrated. As the size of the ions increases, their polarizing power decreases. Hence, other alkali metal ions usually form anhydrous salts.
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