Question

71.587 grams of KCl are dissolved in 1.947 L of water. What is the molarity of this solution?

Answer 1

To calculate the molarity of a solution, we need to use the formula

which is:

Molarity = moles of solute / liters of solution

First, we need to calculate the moles of KCl in the solution:

m = 71.587 g (mass of KCl)

M = 74.55 g/mol (molar mass of KCl)

moles of KCl = m / M = 71.587 g / 74.55 g/mol = 0.9607 mol

Next, we have to calculate the liters of solution:

V = 1.947 L

since we found solute and solution then we can put it into the formula

Molarity = moles of solute / liters of solution

Molarity = 0.9607 mol / 1.947 L = 0.4939 M

Therefore, the molarity of the KCl solution is 0.4939 M.