Choose the correct order of density of the alkali metals

Reaction of ${\mathrm{BeCl}}_2$ with ${\mathrm{LiAlH}}_4$ gives :

(A) ${\mathrm{AlCl}}_3$

(B) ${\mathrm{BeH}}_2$

(C) $\mathrm{LiH}$

(D) $\mathrm{LiCl}$

(E) ${\mathrm{BeAlH}}_4$

Choose the correct answer from options given below

Given below are two statements: one is labelled as Assertion A and the other is labelled as Reason $\mathrm{R}$. Assertion $\mathrm{A}$ : $\mathrm{LiF}$ is sparingly soluble in water. Reason $\mathrm{R}$ : The ionic radius of ${\mathrm{Li}}^{+}$ ion is smallest among its group members, hence has least hydration enthalpy.

In the light of the above statements, choose the most appropriate answer from the options given below.

Given below are two statements:

Statement I : The chlorides of $\mathrm{Be}$ and $\mathrm{Al}$ have Cl-bridged structure. Both are soluble in organic solvents and act as Lewis bases.

Statement II: Hydroxides of $\mathrm{Be}$ and $\mathrm{Al}$ dissolve in excess alkali to give beryllate and aluminate ions. In the light of the above statements. Choose the correct answer from the options given below.

Statement I: An alloy of lithium and magnesium is used to make aircraft plates.

Statement II : The magnesium ions are important for cell-membrane integrity.

In the light the above statements, choose the correct answer from the options given below