Question

Assertion :$L{i}^{+}$ forms series of trihydrates $LiX\cdot 3H_{2}O[X=Cl,Br,I,Cl{O}_2,Cl{o}_4,Mn{O}_4,N{O}_3,B{F}_4)$ Reason: This is due to its smaller size $\left(L{i}^{+}\right)$ and highest ion dipole interaction.

• A. Both Assertion and Reason are correct and Reason is the correct explanation for Assertion
• B. Both Assertion and Reason are correct but Reason is not the correct explanation for Assertion
• C. Assertion is correct but Reason is incorrect
• D. Assertion is incorrect but Reason is correct

Answer 1

The correct option is A Both Assertion and Reason are correct and Reason is the correct explanation for Assertion

The anomalous behaviour of lithium is due to the : (i) exceptionally small size of its atom and ion, and (ii) high polarising power (i.e., charge/ radius ratio ). As a result, there is increased covalent character of lithium compound which is responsible for their solubility.
Because of this, lithium itself, and also its compounds are more heavily hydrated than those of the rest of the group. Example: LiCl is deliquescent and crystallises as a hydrate, $LiCl.3H_{2}O$.