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A bit of Chemistry help

:hello:

Hey, I just need someone to explain how work this question out...I really don't understand what this is asking me to do :s-smilie:

Antimony, Sb, is found naturally in a number of minerals including stibnite. Stibnite typically contains 5% of Sb2s3. Antimony can be obtained by reducing Sb2S3, with scrap Iron

Sb2S3 + 3Fe --------> 2Sb + 3 FeS

(i) How many moles on Sb2S3 are in 500kg of a typical sample of stibnite containing 5% by mass of Sb2S3?

Molar mass of Sb2S3 = 340g
RAM of Sb = 122



(ii)

Calculate the mass of antimony that could be obtained by processing 500kg of stibnite.
Reply 1
(i) Well if there's 5% of the total mass being stibnite, that means there is:
0.05 x 500,000 = 25,000g of Sb2S3

Then you should be able to use the moles = mass/mr to solve that.

(ii) Using the answer from the previous question, and looking at the molar ratio from the balanced equation, you can use the same 'mole' formula to work out how much antimony can be formed..

Does that help?
Reply 2
-David-
(i) Well if there's 5% of the total mass being stibnite, that means there is:
0.05 x 500,000 = 25,000g of Sb2S3

Then you should be able to use the moles = mass/mr to solve that.

(ii) Using the answer from the previous question, and looking at the molar ratio from the balanced equation, you can use the same 'mole' formula to work out how much antimony can be formed..

Does that help?


ahh...i understand what it means now:biggrin: ...the 5% was just confusing me...personally I think the question is just phrased in a stupid way.
Anyways...thanks for your help:smile:
Reply 3
No problem, good luck!
Reply 4
I got 73.53 (approximately) for the number of mole

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