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Small respiration task in class

  1. Dec 10, 2005 #1
    Hi, we did a small respiration task in class and now I need to calculate a few things.

    I placed a bottle of NaOH in another bottle, together with a bottle of yeast and glucose. I did the same with another bottle, but without the yeast/glucose. Amount of glucose 0.2g.

    Now I need to calculate how much CO2 has been produced and how much maximum can be produced.

    I also need to know if there was enough O2 in the bottle to let the glucose react completly (bottle is 440ml). And if there wasn't to much CO2 in the bottle which gives a false result.

    I also needed to know how much NaOH has been used.

    What I have so far:
    Titer of NaOH of bottle yeast/glucose: 0.089N
    Titer of NaOH whithout yeast/glucose: 0.071N
    NaOH used: 0.089N - 0.071N = 0.027N

    Reaction of glucose with O2

    I'm not sure if those are right :uhh:

    Thanks :smile:
  2. jcsd
  3. Dec 15, 2005 #2


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    You're equation needs some fixing, check the number of elements on each side and see if they balance.
    (Ex: left side H = 12, right side H = 8)

    As far as the rest of your question, I don't follow your description. You placed a bottle of NaOH in another bottle, together with a bottle of yeast and glucose. It sounds like you have a big bottle with two little bottles sitting inside it, one with NaOH in it and the other with yeast/glucose. Is the big bottle then sealed or open? Are the small bottles sealed or open? Did I describe your setup correctly?

    I don't know if your NaOH or your 'yeast/glucose' are all solid or if they are solutions. If they are solutions, what volume of liquid is there in each? You mentioned that the bottle is 440ml. Is that its capacity? The reason we need to be clear on this is because you are then given values of normality for two titers. Do you know what normality is?
    Last edited: Dec 15, 2005
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