Dismiss Notice
Join Physics Forums Today!
The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

Homework Help: Vitamin C coursework help

  1. Nov 30, 2008 #1
    Hello there, I just needed help on this following problem, its a biology coursework i am doing and it states that,
    The 1% vitamin C Solution contains 1mg of vitamin c in 1.0cm3. Calculate the mass of vitamin c that is required to decolourise 1cm3 of the DCPIP solution. then use this value to work out how much vitamin c each of the fruit juices contain, in mgcm-3


    So far I have tested all my fruit juices using my burette and I have recorded the volumes that is needed to decolourise the DCPIP. my writeup is almost complete except for this problem that is asking me to do.

    But one thing is i don't understand the question above is asking me
     
  2. jcsd
  3. Nov 30, 2008 #2

    Borek

    User Avatar

    Staff: Mentor

    Do you know what chemical reaction takes place in your solution? This is a stoichiometry problem, you should start with the reaction equation.
     
  4. Nov 30, 2008 #3
    well I had a test tube and inside was 1cm3 of DCIPIP and my burette contained orange juice and had to slowly add drop by drop to the dcipip until it change colour.
    I have to repeat the exact same procedure with grapefruit juice, blackcurrent juice, and a wide range of juices.
     
  5. Nov 30, 2008 #4

    Borek

    User Avatar

    Staff: Mentor

    You are referring to the procedure. I am asking what chemicals do you mix and how do they react.
     
  6. Nov 30, 2008 #5
    There were no chemicals involved, it's just those 2 solutions and when they react, it turned from blue to pinkish colour.
    I mixed the orange juice with the DCPIP and then it changed colour.
     
  7. Nov 30, 2008 #6

    Borek

    User Avatar

    Staff: Mentor

    Every single thing you deal with in your life is made of chemicals. You are made of chemicals - proteins, fat, water, carbohydrates, nucleic acids and mineral salts. Both your solutions were full of chemicals.

    DCPIP is one of chemicals involved. You have already named another one earlier.
     
  8. Dec 1, 2008 #7
    So what do you suggest I should do into calculating the mass?
     
  9. Dec 1, 2008 #8

    Borek

    User Avatar

    Staff: Mentor

    See my first post in the thread.
     
Share this great discussion with others via Reddit, Google+, Twitter, or Facebook