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Need help calculating percent composition

  1. Jun 5, 2005 #1

    I need some help calculating the pecent composition of casien and lactose in milk. I started out with 50ml of nonfat milk, at the end of the experiment I got 1.599g casien and 1.610g of lactose. My idea was to convert these values into ml using density but I could not find the densities. Can someone lead me in the right direction.
  2. jcsd
  3. Jun 5, 2005 #2
    if you are doing % composition by weight, then what is the weight of 50ml of milk? that would be all that you would need.
  4. Jun 5, 2005 #3
    Thats the problem, I just used 50ml of milk, i did not weigh it. The procedure I was following just said to use 50ml of milk, it did not say anything about weighing it.
  5. Jun 6, 2005 #4


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    Staff: Mentor

    You may give your results as % w/v - stupid and rather faulty units, but better then nothing.
  6. Jun 8, 2005 #5
    I actually figure it out. The procedure I was using did not give the density of milk, but one of my classmates had a different version of the procedure which gave the density. That was the only reason i was having this problem. I did not know the density. Thanks for your guys help
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