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Yield & Purity
1)A 12.00g sample of a crystallised pharmaceutical product was found to contain 11.57g of the active drug.
Calculate the % purity of the sample of the drug.
2) What is the % yield of NH3 if 40.5 g NH3 is produced from 20.0 mol H2 and excess N2?
3) 4.4FeS2 + 11O2
–> 2Fe2O3 + 8SO2
If 300 g of FeS2 is burned into 200 g of O2, to produce 143 g Fe2O3 results.
% yield Fe2O3?
4) What mass of impure zinc metal having a purity of 89.5% is required to produce 975 mL of hydrogen gas at RTP according to the reaction.
Zn + HCl à ZnCl2 + H2
Mark Scheme
1) 96.4%
2)17.8%
3) 78.8%
4)3.18g Zn (impure)
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