Explain how you would prepare 500.0 mL of a 0.100 mol/L solution of magnesium sulfate from the solid compound. Show all relevant calculations.
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Because you have the volume and the concentration you can calculate the number of moles of mag sulfate that is needed. Once you have the moles you can calculate the mass
moles = 0.500 L x 0.100 mol/L = 0.0500 moles
Mass = moles x molar mass
mass = 0.0500 moles x 120.37 g/mol = 6.0165 g
So you would gram a 500 mL volumetric flask, put into it 6.0165 g of Mg SO4 and then add about 250 mL of water. Dissolve the solid, then add the rest of the water up to the "scratch" line. Cork the flask and invert several times to thoroughly mix the solution.
moles = 0.500 L x 0.100 mol/L = 0.0500 moles
Mass = moles x molar mass
mass = 0.0500 moles x 120.37 g/mol = 6.0165 g
So you would gram a 500 mL volumetric flask, put into it 6.0165 g of Mg SO4 and then add about 250 mL of water. Dissolve the solid, then add the rest of the water up to the "scratch" line. Cork the flask and invert several times to thoroughly mix the solution.