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Homework Help: Analytical Chem Problem

  1. Sep 16, 2011 #1
    1. The problem statement, all variables and given/known data
    The following data were obtained for the analysis of soil for vanadium content in mg/g using two different methods. Do the two methods yield essentially the same results?

    Method 1 Method 2
    26.30 26.22
    26.43 26.32
    26.28 26.20
    26.19 26.11
    26.49 26.42

    2. Relevant equations
    I'm thinking I find the mean and standard deviation of each, find spooled and from there I'm not sure. So I know those 2 formulas, but I;m not sure on any others..

    3. The attempt at a solution
    Didn't attempt because I kind of need a push in the right direction, not someone to do out the problem..
     
    Last edited: Sep 16, 2011
  2. jcsd
  3. Sep 17, 2011 #2

    Redbelly98

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    FYI, I have moved your 2 recent statistics questions to "Precalculus Mathematics".

    Looks like a t-test is needed here. There should be something in your textbook or class notes about comparing two sample means.

    p.s. welcome to Physics Forums.
     
  4. Sep 17, 2011 #3
    thank you!
    i cant really find anything in my textbook, and the only reason im unsure on how to do this is because i was really sick for the class so i didnt get to go, but im still required to pass the assignment in, so im legit lost :(
     
  5. Sep 17, 2011 #4

    Redbelly98

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    When you know the right search terms, Google gives a lot of hits:

    http://www.google.com/#hl=en&sugexp...pw.r_cp.&fp=93057ccd64abdef9&biw=1280&bih=678

    Or check this wikipedia page; scroll down to the section titled "Independent two-sample t-test":
    http://en.wikipedia.org/wiki/Student's_t-test#Independent_one-sample_t-test

    By the way, it's a good idea to ask a classmate if you could copy their class notes whenever you have to miss a class.

    EDIT: out of curiosity, is this a statistics or a chemistry class (or something else)?
     
    Last edited: Sep 17, 2011
  6. Sep 17, 2011 #5
    Thanks a lot!

    It was the second day of classes (terrible time to come down with the flu), and I don't know anyone in the class, the professor just e-mailed me the assignment and still wants me to hand it in on time without notes. That's another story though.

    It's an analytical chemistry class, so I guess the introduction is mainly statistics (which I never took, so I'm even more lost). It's a terrible situation really.

    EDIT: That wikipedia link looks perfect for what I have to do.. thanks a lot!!! Also, any idea on the other question I posted? :-)
     
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