Question

What is the molarity of a solution containing 150 g of zinc sulfate (ZnSO4) per liter?

Answer 1

0.93 M

Explanation:

First, we have to calculate the molar mass (MM) of ZnSO₄ by using the molar mass of each chemical element:

MM(ZnSO₄) = 65.4 g/mol Zn + 32 g/mol S + (16 g/mol x 4) = 161.4 g/mol

Then, we divide the mass of ZnSO₄ into its molar mass to obtain the number of moles:

moles ZnSO₄ = mass/MM = 150 g/(161.4 g/mol)= 0.93 mol

Since the molarity of a solution expresses the number of moles of solute per liter of solution, we calculate the molarity (M) as follows:

M = moles ZnSO₄/1 L = 0.93 mol/1 L = 0.93 M