Answer to Question #209301 in General Chemistry for Neil

Question

The calcium and magnesium in a urine sample were precipitated as oxalates. A mixed precipitate of CaC2O4 and MgC2O4 resulted was heated to form CaCO3 and MgO. This second mixture weighed 0.0433g. After ignition to form CaO and MgO, the resulting solid weighed 0.0285g. What was the sum of masses of Ca and Mg in the original sample?

Answer 1

m=0.0433g-0.0285g=0.0148g

m=0.0433g+0.0148g=0.0581g