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MC: Chemistry Ideal Gas vs Real Gas

  1. Mar 5, 2009 #1
    1. The problem statement, all variables and given/known data

    24. At constant temperature, the behavior of a sample of a real gas more closely approximates that of an ideal gas as its volume is increased because the:
    a. Collisions with the walls of the container become less frequent
    b. Average molecular speed decreases
    c. Average distance between molecules becomes greater
    d. Average molecular kinetic energy decreases

    2. Relevant equations


    3. The attempt at a solution
    I know when volume is increased, pressure is decreased (due to constant temp). And real gases behave most like ideal gases at low pressure. And real gases have small volume.. so I'm confused.
    Through process of elimination I came to the answer of C. I'd like to know if it is correct and/or if there is a better way of approaching the problem.

    Thanks so much! =]
  2. jcsd
  3. Mar 5, 2009 #2


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    Ideal gases have no size - if you have a container of real molecules what can you do to make their physical size less important?
  4. Mar 5, 2009 #3
    separate them so they experience no charge/attraction on each other?
    I still feel like the answer is C, am i incorrect?

    The only possible choices are A and C

    kinetic energy is effected by temp and speed has nothing to do with volume..?
  5. Mar 5, 2009 #4


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    Correct - at larger volumes (ie lower pressure) the the molecules take up a smaller percentage of the container and so are less likely to hit each other.
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