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Stoichiometry Mole Conversion Problems

  1. Feb 20, 2006 #1
    Hey there, I've been trying for the past 45 minutes to work on my online homework but I have made hardly any progress. Here are the 2 problems I'm having trouble with:

    1- Calculate the number of molecules of NBr3 in 37.5 g NBr3. Use a molar mass with at least as many significant figures as the data given.

    2-CH4(g) + Cl2(g) --> CHCl3(l) + HCl(g)

    What mass of HCl can be produced from 1.60 g of methane and 10.0 g of chlorine in the above unbalanced reaction? Use at least as many significant figures in your molar masses as in the data given.

    The problem in the first one is that I'm going from mass to molecules. I've only done problems involving moles and mass. Any hints as to how to get started?

    For the second one, I think I balanced the equation right. 2CH4 + 6Cl2 --> 2CHCl3 + 6HCl? I also see the problem is converting mass to mass. However, with methane AND chlorine involved, I'm lost as to where to go from here.

    All help is appreciated, thanks!
    Last edited: Feb 20, 2006
  2. jcsd
  3. Feb 21, 2006 #2
    *Groans* I'm doing exactly that in my online course.:yuck:

    In case this helps you (It didn't help me but I'm convinced I'm just slow...:tongue: ), here is what we were given...

    http://dbhs.wvusd.k12.ca.us/webdocs/Stoichiometry/Stoichiometry.html [Broken]


    I'll have to look over it again myself.:smile:
    Last edited by a moderator: May 2, 2017
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