My chem question

[vraj120195]

Hey guys I needed help with this question can somebody please help. Thanks

The sulfur content of coal may be estimated by igniting the sample of coal with Na2CO3 and then, by suitable treatment, converting the sulfur present to a precipitate of BaSO4. If, in a particular analysis, a 2.00g sample of coal yields 0.493g of Barium Sulfate, what was the percentage by mass of sulfur in the coal?

+1 Karma

[Russ]

Calculate moles of BaSO4 (n = m/M)

Calculate moles of S (stoich ratio)

Calculate mass of S (m = n * M)

Calculate percentage mass of S in the coal (m/2 * 100/1)

[huaxiadragon]

Just to provide you with answers. Here's what I got

n(BaSO4)=0.493g/(137.1+64+32.07)=0.0021125

n(S)=0.0021125

m(S)=0.0021125 * 32.07=0.06775g

%m/m=(0.06775/2.00) * 100=3.38%

I'm doing this using computer calculator so there may be some error

[vraj120195]

Thanks guys