Question

Nitric acid is usually purchased in concentrated form with a 70.3% HNO3HNO3 concentration by mass and a density of 1.41 g/mLg/mL. Part A How much of the concentrated stock solution in milliliters should you use to make 2.0 LL of 0.500 MM HNO3HNO3 ?

Answer 1

Answer:

V = 63.57 mL

Explanation:

In this case, to get the mL of the stock nitric acid we need to know first the concentration in mol/L so it can match the units of the desired concentration, in this case, 0.5 mol/L

To get the concentration of the stock solution, we should use the following expression:

M = % * d * 1000 / MM * 100

The molar mass of the nitric acid (HNO₃) is:

MM = 1 + 14 + 3(16) = 63 g/mol

the concentration of the acid is:

M = 70.3 * 1.41 * 1000 / 63 * 100

M = 15.73 M

Now that we know the concentration of the solution, we use the following expression to get the volume:

M1*V1 = M2*V2

Replacing the values and solving for V1 we have:

V1 = M2*V2 / M1

V1 = 2 * 0.5 / 15.73

V1 = 0.06357 L

In mL it will be:

V1 = 0.06357 * 1000 = 63.57 mL