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Homework Help: Mole problems

  1. Nov 28, 2007 #1
    1. The problem statement, all variables and given/known data



    *How many moles of LiH are required to make 1 mole of LiAlH4?


    * 6 moles of LiH will produce how many moles of LiAlH4?


    Can someone help me get started on these?
     
  2. jcsd
  3. Dec 2, 2007 #2

    Gokul43201

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    You start by writing the balancing the relevant equation. Can you do that for the above reaction?
     
  4. Dec 5, 2007 #3
    I am learning the same stuff in class, I can clearly see from what is written that there is a 4 to 1 ratio, so I think we get 1.5 moles. What I don't see is how the equation works. I wrote it out and somethings seems missing.
    LiH + Alxx ----> LiAlH4 + xx
    I got myself a bit confused, should there be something for xx or is it just Al?

    P.S. I would not normally encroach on someone elses question, but since two weeks have passed, I figured it would be ok.
     
    Last edited: Dec 5, 2007
  5. Dec 6, 2007 #4

    Gokul43201

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    Good thinking. Alxx is actually [itex]AlCl_3[/itex].
     
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