Chemical Forums
Chemistry Forums for Students => Undergraduate General Chemistry Forum => Topic started by: Reviction on February 27, 2013, 12:54:36 AM
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Howdy!
Two quick questions.
I was having to plot a graph based off pressure vs volume. The result I got was a negative declining slope that is not a straight line but curves ever so slightly. Is that considered a type of parabola? That was a question on my lab report but it's been nearly 5 years since I've had a math class.
On that note, what I was graphing was room airs volume vs pressure. If I changed the gas to CO2 (didn't have dry ice on me to test) instead of air. Would the slope be steeper/less steep, directly related to volume/pressure, no difference as Boyles law works for all gases, or Boyles law doesn't apply due to CO2 being too dense.
On the second question, I am leaning to it being "directly related" or "no difference." I don't see the steep changing or CO2 being to dense to use Boyles law.
Thanks for any thoughts!
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If the gas behaves as an ideal gas, its identity doesn't matter. At room temperatures gases are not ideal, but relatively close to. Not sure if you should be able to see the difference between different gases - most likely it is a matter of how precise your measurements are (if you are precise enough, the difference will be there for sure).
It is possible to use Van der Waals equation to estimate these differences, but I suppose if you are learning about Boyles law, Van der Waals equation will be out of this world...