[gotalbin]

A 3.00 g sample of an alloy  (containing Pb and Sn) was dissolved in nitric acid (HNO₃. Sulfuric acid was added to this solution, which precipitated 2.93 g of PbSO₄. Assuming that all of the lead was precipitated, what is the percentage of Sn in the sample?

Do we find the amount of grams in lead by dividing 207 by its molecular weight (303.3) and then multiplying by 2.93 to get 1.99 grams of Lead in Lead sulfate. I am not sure this is right. Please help.

[DevaDevil]

how many moles is 2.93 g. of lead sulfate?

then how many original grams of lead would that have been.

then you have the mass% of lead, and also the mass% of Sn

[gotalbin]

wait im not sure i understand...find the number of moles for lead sulfate and then do what?

[Borek]

wait im not sure i understand...find the number of moles for lead sulfate and then do what?

Than how many grams of lead do you have in this sulfate.