Question

It is a data sufficiency problem in which it is to be decided on the basis of given statements whether the given question can be answered or not (no matter whether the answer is yes or no). If $\Delta H_{solution}<0$ then compound acts as ionic in aqueous solution. Is $AlC{l}_3\left(s\right)$ ionic in aqueous solution.
Statement 1 : L.E. of $AlC{l}_3\left(s\right)$ is 5137 kJ/mol
Statement 2 : $\Delta H_{HE}ofA{l}^{+3}$ ion is -4665 kJ/$mo{l}^{-1}$ & $\Delta H_{HE}ofC{l}^{-}$ is -381 kJ/$mo{l}^{-1}$

• A. Statments (A) alone is sufficient but statement (B) is not sufficient
• B. Statments (B) alone is sufficient but statement (A) is not sufficient
• C. Both statement together are sufficient but neither statement alone is sufficient
• D. Statement (A) & (B) together are not sufficient

Answer 1

Answer: (C)

Both statement together are sufficient but neither statement alone is sufficient

Both statements together are sufficient but neither statement alone is sufficient. From the statements 1 and 2, the heat of solution of AlCl3 can be calculated from which, it can be decided that it is ionic or not in aqueous solution. To calculate the heat of solution, the data required is the lattice enthalpy of the compound and the hydration energies of the cation and the anion.