Question

What is the concentration of an AlCl3 solution if 150 ml of the solution contains 450 mg of Cl- ion?

a. 2.82 × 10^-2 M AlCl3
b. 2.54 × 10^-1 M AlCl3
c. 6.75 × 10^-2 M AlCl3
d. 8.46 × 10^-2 M AlCl3

Answer 1

To find the concentration of the AlCl3 solution, divide the number of moles of AlCl3 by the volume of the solution.

Step-by-step explanation:

To find the concentration of the AlCl3 solution, we need to convert the mass of Cl- to moles and then use the balanced chemical equation to relate it to AlCl3. First, calculate the number of moles of Cl- by dividing the mass (450 mg) by its molar mass. Next, use the balanced chemical equation 2Al + 3Cl2 → 2AlCl3 to determine the number of moles of AlCl3. Since there is a 3:2 ratio of Cl2 to AlCl3, multiply the moles of Cl- by 2/3 to get the moles of AlCl3. Finally, divide the moles of AlCl3 by the volume of the solution (150 mL converted to L) to get the concentration in Molarity (M).

The concentration of the AlCl3 solution is 0.0298 M (option a).