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Homework Help: Prove the relationship between kPa and mmHg?

  1. Jul 18, 2012 #1
    I suppose this is more of a math question, but it's a bonus question in my chemistry upgrade class.

    1. The problem statement, all variables and given/known data
    Prove the relationship 760mmHg=101.35kPa mathematically, by using conversion factors.

    2. Relevant equations
    1 Pa=1 kgm/s2 (No it doesn't?...)
    density of Hg=13.6g/cm3
    acceleration due to gravity=9.8m/s2

    3. The attempt at a solution
    I'll be honest, my mind is totally blanking on this, I know my math skills should be able to handle this no problem, but it feels like all my math skills have ran away for the summer. I mean yeah I can convert 101.35kPa into an area using gravity I guess, but I'm not sure what that tells me. While telling me how to get the answer would be great, I'd even be happy with a hint at where to get start.
  2. jcsd
  3. Jul 18, 2012 #2


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    2017 Award

    You have a column of mercury sitting on a one meter by one meter square that is 760 mm high. What is the pressure on that square in kPa?
  4. Jul 23, 2012 #3
    This question was a lot easier than it felt at the time, just stepped entirely away from chemistry for a bit and looked at it as a math problem, what you said helped me get into the right mindset. I even got an extra mark for pointing out the mistake in the problem. (1 Pa equals 1kg/s2m, not 1kgm/s2)
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