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: Significant Figures.

  1. Mar 17, 2007 #1
    When i have a conversion fact such as,

    [tex]6.45 mol H_{2\left(g\right)}\times\frac{2 mol HBr_{\left(g\right)}}{2 mol H_{2\left(g\right)} }= 12.9 mol HBr_{g}[/tex]

    how many significant figure should the answer have?, im thinking one.
     
    Last edited: Mar 17, 2007
  2. jcsd
  3. Mar 17, 2007 #2

    cristo

    User Avatar
    Staff Emeritus
    Science Advisor

    You've not written one sig fig though, you've written your answer with three. I would suggest to use 3 sig figs since the number of moles of hydrogen are accurate to 3 sig figs, and I presume that 2 is exactly two (i.e. 2.000), so giving 3 sig figs in the answer (like you've done; 12.9) will be as accurate as possible.
     
  4. Mar 17, 2007 #3
    thanks cristo.
     
Share this great discussion with others via Reddit, Google+, Twitter, or Facebook