Difference in calculating molar masses

asked by @linhl13 • about 1 year ago • Chemistry • 5 pts
  1. Calculate the pressure (atm) of 1 mole of hydrogen gas at 298 K using the ideal gas law for a 50.0 mL flask.

vs.

  1. Calculate the pressure (atm) of 1 mole of hydrogen gas at 298 K using the Van der Waals equation for a gas in a 1.00 L flask.

What's the difference between these two questions?

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1 answer

Hi there! As we know, gases don't exist as ideal gases but as real gases. Ideal gas uses PV=nRT as its equation while real gases uses Van der Waals equation, it's kind of similar to the ideal gas law but there are some modifications. Another things is that VdW equation uses a series of constant for gases which is present as variables a and b.

So instead of using the simple PV=nRT, we will use a more complicated equation whenever we want to use the real gas equation. I attached the formula of VdW gas equation. Hope that clears things up! enter image description here

answered by @reyn • about 1 year ago
  • Thank you, I'm still a little bit confused for Van der Waals. Can you demonstrate both problems given so that I can easily identify the difference? Linh commented about 1 year ago