1. Limited time only! Sign up for a free 30min personal tutor trial with Chegg Tutors
    Dismiss Notice
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: 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


    User Avatar
    Staff Emeritus
    Science Advisor
    Homework Helper

    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


    User Avatar
    Staff Emeritus
    Science Advisor
    Homework Helper

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


    Or check this wikipedia page; scroll down to the section titled "Independent two-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? :-)
Share this great discussion with others via Reddit, Google+, Twitter, or Facebook