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A mol question

  1. Apr 13, 2005 #1
    how do you work out the amount of mole Chlorine ions in 13.4g of nickel chloride(NiCl2). i don't know how to use the n=m/M with ions?
  2. jcsd
  3. Apr 13, 2005 #2


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    [tex](mass NiCl_2)(\frac{1 mole NiCl_2}{grams NiCl_2})(\frac{moles Cl}{moles NiCl2})[/tex]

    put some values into the equation and everything should work out.
    I really wish Latex understood what a space bar does.
  4. Apr 13, 2005 #3
    [tex](mass \ NiCl_2)(\frac{1 \ mole \ NiCl_2}{grams \ NiCl_2})(\frac{moles \ Cl}{moles \ NiCl2})[/tex]

    Try adding \ in between the words you want seperating.

    Back to the question. Personally (maybe because my knowledge of equations is not as great as some) I would find the percentage of chlorine in the coumpound by using the molar mass of the coumpound and the two elements in it. Then I would find the mass of chlorine (using the percentage) and then find how many moles that was by dividing by the molar mass of chlorine.

    The Bob (2004 ©)
    Last edited: Apr 13, 2005
  5. Apr 15, 2005 #4
    Whenever it comes to calculating moles, mass, molarity etc. always use units as a guide. What you have now is 13.4g NiCl2, and how to convert from g to moles.

    From the periodic table, you can calculate the molar mass of NiCl2 to get 1 mol / ?g NiCl2. Also, how many moles of Cl are there in 1 mol of NiCl2?

    13.4g NiCl2 x 1mol NiCl2 / ?g NiCl2 x ?mol Cl / 1mol NiCl2 = no of mol Cl

    Hope this helps! :smile:
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