A stock solution containing Mn2+ ions was prepared by dissolving 1.168 g pure manganese metal in nitric acid and diluting to a final volume of 1.000 L. Calculate the concentration of the stock solution.
mols Mn = grams/atomic mass
M = mols/L soln.
To calculate the concentration of the stock solution, we need to determine the number of moles of Mn2+ ions in the solution and then divide it by the volume of the solution.
First, we need to calculate the number of moles of Mn2+ ions present in 1.168 g of pure manganese metal. To do that, we'll need the molar mass of manganese (Mn), which is 54.94 g/mol.
Number of moles = mass / molar mass
Number of moles = 1.168 g / 54.94 g/mol
Number of moles ≈ 0.0212 mol
Next, we divide the number of moles by the volume of the solution (1.000 L) to find the concentration:
Concentration (M) = number of moles / volume (L)
Concentration (M) = 0.0212 mol / 1.000 L
Concentration (M) ≈ 0.0212 M
Therefore, the concentration of the stock solution is approximately 0.0212 M.