Final answer:
To determine the mass percent of MgSO4 in the mixture, calculate moles of BaSO4, apply stoichiometry to find moles of MgSO4, then express the mass of MgSO4 as a percentage of the total mixture mass, yielding 69.89%.
Step-by-step explanation:
To calculate the concentration (mass percent) of MgSO4 in the mixture, we need to connect the moles of BaSO4 to the moles of MgSO4. First, we calculate the moles of BaSO4 using the precipitate's mass and its molar mass:
moles of BaSO4 = mass of BaSO4 / molar mass of BaSO4
moles of BaSO4 = 0.6168 g / 233.39 g/mol
moles of BaSO4 = 2.64 x 10-3 mol
Since the stoichiometric ratio between MgSO4 and BaSO4 is 1:1, the moles of MgSO4 will be the same. We then calculate the mass of MgSO4:
mass of MgSO4 = moles of MgSO4 x molar mass of MgSO4
mass of MgSO4 = 2.64 x 10-3 mol x 120.37 g/mol
mass of MgSO4 = 0.318 g
To find the mass percent, divide the mass of MgSO4 by the mass of the sample mixture and multiply by 100:
mass percent MgSO4 = (mass of MgSO4 / mass of sample mixture) x 100
mass percent MgSO4 = (0.318 g / 0.4550 g) x 100
mass percent MgSO4 = 69.89%
Therefore, the mass percent of MgSO4 in the mixture is 69.89%.