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Simple chemistry problem

  1. Dec 16, 2003 #1
    Normally i wouldnt post this in here and im very sorry if im breaking any rules but i need quick help or im toast. Allready posted in the chem forum but im afraid it will take to long to get an answer.

    I need to return an asignment today and i just cant figure it out (should probably be a piece of cake for the people that hangs around here)

    There is 10ml HCl with an unknown concentration i a beaker. You let NaOH with the concentration 0,100 mol/dm3 drip into the acid untill it is neutralized.
    It takes 10,5ml NaOH to neutralize the acid.

    With this you should be able to calculate the concentration of the acid or so my teacher say. And all i can do is sit here and look dumb while my brain refuses to cooperate

    Could anyone help me i would owe you a life debt. If i dont get this in today i wont get a grade in chemistry
  2. jcsd
  3. Dec 16, 2003 #2
    Apply the normality equation


    Here normality is equal to Molarity

    Hence Concentration is either given by normality/molarity

    Stength is given by Molarity*Molecular Weight
  4. Dec 16, 2003 #3
    Ok, just to check.

    So i take
    10,5ml * 0,1 = 1,05
    10 * x = 1,05
    1,05 / 10 = 0,105
    10 * 0,105 = 1,05

    So the concentration of HCl is 0,105mol/dm3 or have i gotten it completley wrong?

    *edit* After checking that over i dont think it can be that simple.
    I know that knowing what type of acid it is is instrumental to the calculations and this dont involve that at all so im dead wrong.
    Back to square one :(
    Last edited: Dec 16, 2003
  5. Dec 16, 2003 #4
    Yes it is correct and it is that simple.

    I believe u know the equation that i quoted
    It definitely gives correct results
  6. Dec 16, 2003 #5
    ...Wow. I managed to get it right
    I thank you for helping me out. Without that little kick in the right direction i wouldnt have manged to solve it.
    Thank you again, i owe you.
  7. Dec 16, 2003 #6
    u owe me
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