Question

A soln containing 439.4 g of Mg(NO3)2 (148.3 g/mol) per liter has a density of 1.114 g/mL. What is the molarity of the solution?

Answer 1

Solution :-

lets assume we have 1 L solution

so the mass of the Mg(NO3)2 = 439.4 g

lets calculate the moles of Mg(NO3)2

moles = mass / molar mass

moles of Mg(NO3)2 = 439.4 g / 148.3 g per mol

                             = 2.963 mol Mg(NO3)2

now lets calculate the molarity

molarity = moles / volume in liter

              = 2.963 mol / 1 L

               = 2.963 M

So the molarity of the solution is 2.963 M