Question

Between $AlF_{3}$ and $AlCl_{3}$ which one will have a higher melting point.

Answer 1

The melting point is directly depends upon the intermolecular bonds that are present in the compound.  

The melting point of $Al{ F }_{ 3 }$ is 1290℃ and $Al{ Cl }_{ 3 }$ is 178℃.  

i) Aluminium fluoride is ionic in character, due to its low polarisability of the fluoride ion, so it has a high melting point.  

ii) Aluminium chloride is covalent in nature due to the high polarising power of aluminium, so it has a low melting point.  

iii) Aluminium chloride does not have a melting whereas it sublimes.