Dismiss Notice
Join Physics Forums Today!
The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

Homework Help: An Ore contains 19.6 %

  1. Sep 13, 2012 #1
    An Ore contains 19.6 %....

    Question:

    An ore contains 19.6% of the mineral stibnite, Sb2S3, which is a source of the element Sb. how much ore must be processed in order to obtain 47.0kg of Sb?


    My Work:

    (47000g Sb)((153.825g Sb2S3/ 2 (121.76 g Sb)) (100g ore/19.6g Sb2S3)

    which equals 151472.5983g
    151.473 Kg



    i just want to know if my though process is correct and if i am suppose to multiply the mass of Sb becasue it has 2 moles ! please let me know ! thanks ! and if my Sig Fig is correct in the final answer
     
  2. jcsd
  3. Sep 14, 2012 #2

    Borek

    User Avatar

    Staff: Mentor

    Re: An Ore contains 19.6 %....

    It is not entirely wrong.

    Yes for 2, but your molar mass of Sb2S3 is completely off. 153.8 would be a molar mass for SbS.

    No. How many sig figs in the data?
     
  4. Sep 14, 2012 #3
    Re: An Ore contains 19.6 %....


    oh ok.. so i multiply my sb by 2 and s by 3 .. (their masses and then add them together like normally)
     
  5. Sep 14, 2012 #4

    Borek

    User Avatar

    Staff: Mentor

    Re: An Ore contains 19.6 %....

    That's how you calculate molar mass, yes.
     
Share this great discussion with others via Reddit, Google+, Twitter, or Facebook