## Chemistry: The Molecular Science (5th Edition)

The pH of an $AlCl_3$ solution will be less than 7. This happens because, this salt is formed by a Lewis acid $(Al^{3+})$ and three negligible bases $(Cl^-)$, therefore, the solution is acidic.
To predict the pH range of an salt: 1. Identify the ions that form this salt, and compare its strengths: 1 $Al^{3+}$: Lewis acid. 3 $Cl^-$: Insignificant base. Therefore: $Al^{3+}$ is the stronger electrolyte, so, the solution is acidic.