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: How to convert into moles

  1. Sep 11, 2010 #1
    1. The problem statement, all variables and given/known data
    So I'm trying to solve a problem and it asks: If 1 ml of 10 N NaOH is added to a liter of the buffer prepared, how much will the pH change?
    I know how to solve the problem but one thing is really confusing me, how am I able to convert the 1 ml of 10 N NaOH into moles...like what exactly does 'N' signify...? like supposedly it means avagadro's number. The answer to the number of moles is....0.01 mol OH


    2. Relevant equations



    3. The attempt at a solution
     
  2. jcsd
  3. Sep 11, 2010 #2

    Borek

    User Avatar

    Staff: Mentor

  4. Sep 11, 2010 #3
    Like it says that normality is equivalent/L...but like how am i supposed to get the NaOH in moles?....Do i calculate it as (10 equivalent/L)*(0.01 L)= 0.1 equivalent...but like what does this mean....?
     
  5. Sep 11, 2010 #4

    Borek

    User Avatar

    Staff: Mentor

    Have you heard about google? Wikipedia?

    http://en.wikipedia.org/wiki/Equivalent_(chemistry [Broken])

    Note that wikipedia uses a narrow definition, that is - equivalents are what reacts with 1 mole of H+ or electrons. I prefer other definition - one that takes into account stoichiometry of the given reaction. Hence 1M HCl is always 1N, regardless of the reaction, while 1M H[su]2[/sub]SO4 is sometimes 1N and sometimes 2N, depending on the reaction.
     
    Last edited by a moderator: May 4, 2017
Share this great discussion with others via Reddit, Google+, Twitter, or Facebook