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Homework Help: Moles of Iron and Copper Lab

  1. Feb 13, 2007 #1
    Can someone please verify my results? and help me in one-2 questions?

    I did this lab in school today and had some problems filling in the table that followed.
    In the lab, we took some Copper Chloride and mixed it dionized water. Then we added in an iron nail and waited for about 20 mins. After 20 mins we decanted the water(threw it away) and were left with copper+a lil bit of water which was later dried.
    The following is the data I have

    Mass of Beaker --> 0.906
    Mass of Beaker and Copper Chloride --> 12.44
    Mass of Nail before reaction-->1.729
    Mass of Nail after reaction-->1.444
    Mass of Beaker and dry copper[dry]-->10.345

    The questions that followed were to calculate moles and mass.

    1>Mass of Copper formed.

    For this,it should be 12.44-10.345 =2.095gms

    2>Moles of Copper

    For this I did 2.095/63.5= .329moles

    3>Mass of Iron reacted

    4>Moles of Iron

    5>Ratio of moles of Iron to Copper

    I guess I screwed up on the calculations or something on the Mass of Iron Reacted which gave me .285 gms. This I feel has screwed my moles of Iron up. I dont know where I am going wrong in this.

    If someone can help me out,I would be greatful. I am kinda guessing the mole ration should be 1:1.

  2. jcsd
  3. Feb 13, 2007 #2
    Can Anyone atleast get me started? :cry:
  4. Feb 14, 2007 #3
  5. Feb 14, 2007 #4


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    Everything looks good, except that your calculation for mass of copper is actually the difference in the weight of copper chloride and formed copper. The answer is correct but that question was not asked.

    All of your problems are solved if you can find a weigh to determine the mass of copper.

    Copper chloride is not copper.
  6. Feb 14, 2007 #5
    I messed up on the Mass of the beaker. it should read 9.906 above and not .906

    In the end when we dried the copper from the dionized water,I massed it and got 10.345gms for copper.

    The mole ration after calculation is a high number and not 1:1 or 2:3. I am sure something is wrong.
    Last edited: Feb 14, 2007
  7. Feb 15, 2007 #6


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    Answer the first question!
  8. Feb 15, 2007 #7
    First Question?

    So copper should be =10.345-9.906-->.439gms
  9. Feb 16, 2007 #8


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    Couple that answer with your obvious skill in problem-solving and you are done with this problem!

    Now answer #2 and recalculate #5.
  10. Feb 18, 2007 #9


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