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Homework Help: Molarity question

  1. Feb 22, 2010 #1
    if i have a 40 micromolar concentration of stock solution and add .01 mL of that solution to .98mL of water, what is my final concentration.

    Thanks for any help!
     
  2. jcsd
  3. Feb 22, 2010 #2
    What is the final volume of your solution?
     
  4. Feb 22, 2010 #3
    sorry! .99 mL
     
  5. Feb 22, 2010 #4

    Borek

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    Staff: Mentor

    Does the number of moles in the final solution differ from the number of moles in initial solution?

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    methods
     
  6. Feb 22, 2010 #5
    no, same
     
    Last edited: Feb 23, 2010
  7. Feb 23, 2010 #6
    so any help?
     
  8. Feb 23, 2010 #7
    Use the equation relating the initial molarity to the final molarity and volume:

    M1V1 = M2V2
     
  9. Feb 23, 2010 #8

    Borek

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    Staff: Mentor

    My question was a hint. If amount of substance have not changed, why don't you calculate initial amount of substance and use concentration definition to calculate final concentration?

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    methods
     
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