S
Squeakurs
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A mixture contained zinc sulfide, ZnS, and lead sulfide, PbS. A sample of the mixture weighing 6.12 g was reacted with an excess of hydrochloric acid. The reactions are given below.
ZnS(s) + 2 HCl(aq) → ZnCl2(aq) + H2S(g)
PbS(s) + 2 HCl(aq) → PbCl2(aq) + H2S(g)
If the sample reacted completely and produced 1.060 L of hydrogen sulfide, H2S, at 23°C and 745 mmHg, what were the percentages of ZnS and PbS in the mixture?
So far, I have used the Ideal Gas Law to calculate the number of mols of H2S (I got .0428 mol) and then used that and the amu of each to get the predicted mass of each substance... but when I did, my answer told me that there was 4.1 g of ZnS and 10.07g of PbS?
There is only 6.12g of mixture! I even ignored this and went ahead and found the percentages, which was well over 100%, and it was wrong. I have tried several times, and can't get a correct answer, or even one that makes sense!
ZnS(s) + 2 HCl(aq) → ZnCl2(aq) + H2S(g)
PbS(s) + 2 HCl(aq) → PbCl2(aq) + H2S(g)
If the sample reacted completely and produced 1.060 L of hydrogen sulfide, H2S, at 23°C and 745 mmHg, what were the percentages of ZnS and PbS in the mixture?
So far, I have used the Ideal Gas Law to calculate the number of mols of H2S (I got .0428 mol) and then used that and the amu of each to get the predicted mass of each substance... but when I did, my answer told me that there was 4.1 g of ZnS and 10.07g of PbS?
There is only 6.12g of mixture! I even ignored this and went ahead and found the percentages, which was well over 100%, and it was wrong. I have tried several times, and can't get a correct answer, or even one that makes sense!