Preduct that anhyrous `AICI_(3)` is covalent form the data given below, ionisation enegry for `AI = 5137 kJ mol^(-1), Delta_(hyd) H` for `AI^(3+) =- 4665 kJ "mole"^(-1), Delta_(hyd)H` for `CI^(Theta) =- 381 kJ mol^(-1))`

Options

A. The solution will consist of `Al^(+3) & Cl^(-)`
B. The solution will consist of hydrated `Al^(+3) & Cl^(-)`
C. It will remain covalent in aqueous solution
D. None

Answer

B

Explanation

`DeltaH` hydration for `Al^(+3)= -4665 K^(-1)`mol
`DeltaH` hydration for `Cl^(-) = -381` kJ/mol
In `AlCl_(3) to 3Cl^(-)`
so, `DeltaH` hydration for `3Cl^(-) = -381 xx 3 = -843`
Total hydration enthalpy
`=-4665+ -843 = -5508`
Lattice energy = 5137
Hydration energy is more than lattice energy