A chemist prepares a solution of magnesium fluoride MgF2) by measuring out 0.514 mg of magnesium fluoride into a 50. mL volumetric flask and filling the flask to the mark with water.

Question

Calculate the concentration in mol/L of the chemist's magnesium fluoride solution. Be sure your answer has the correct number of significant digits.

Answer 1

To calculate the concentration in mol/L, we first need to convert the mass of magnesium fluoride to moles using the molar mass of MgF2:

Molar mass of MgF2 = (1 mol Mg x 24.305 g/mol) + (2 mol F x 18.998 g/mol) = 62.301 g/mol

Now, convert the mass of MgF2 to moles:

0.514 mg = 0.000514 g
0.000514 g / 62.301 g/mol = 8.25 x 10^-6 moles

Next, calculate the volume in liters:

50 mL = 0.050 L

Now, calculate the concentration:

Concentration = moles / volume
Concentration = 8.25 x 10^-6 moles / 0.050 L = 0.000165 M

Therefore, the concentration of the magnesium fluoride solution is 0.000165 mol/L.