You have 0.672 L of 4.78 M aqueous AlCl3 solution in a glass. If you gently heat the solution until only 0.380 L is left, what is the new molarity of the AlCl3 solution?

8.45 M

Explanation:

To solve this problem we need to keep in mind the definition of molarity:

First we calculate the moles of AlCl₃ in 0.672 L of a 4.78 M solution:

Then we calculate the new molarity of the AlCl₃ solution using that number of moles, which remains the same throughout the evaporation process:

a chemical reaction

explanation: