Question

If 2.94 g of CuNO3 is dissolved in water to make a 0.300 M solution, what is the volume of the solution? Number mL 780 Tools x 102

I got .780mL but it doesn't seem to be the correct answer.

Answer 1

Molarity = moles of solute /volume of solution(l) (molarity = 0.3 M) moles of solute = mass of solute/molar mass For CuNo_3, molar mass = 125.5 g mol^-1 mass = 2.94 g moles = 2.94/125.5 = 0.0234 mol 0.3 = 0.0234/volume of sol(l) volume of solution -0.0234/0.3 = 0.078 l = 7.8 times 10^-2 l 1l = 1000 mL 7.8 times 10^-2 l = 1000 times 7.8 times 10^-2 = 7.8 times 10^1 mL = 78 mL