A solution was prepared by mixing 50.00 mL of 0.100 M HNO3 and 100.00 mL of 0.200 M HNO3.

Question

Calculate the molarity of the final solution of nitric acid.

please explain

Answer 1

There are many ways to solve. This method may be easiest to understand.

50.0 mL x 0.100 M = 5.00 millimoles of HNO3 (0.00500 moles)

100.0 mL x 0.200 M = 20.0 millimoles of HNO3 (0.0200 moles)

The combined solution has a volume of 150.0 mL (50.0+100.0)

The combined solution contains 25.0 millimoles of HNO3 (5.00+20.0)

millimoles / mL = Molarity (25.0 / 150.0 = 0.1667 M)

moles / Liters = Molarity (0.0250 / 0.1500 = 0.1667 M)