What is Ideal gas law: Definition and 238 Discussions

The ideal gas law, also called the general gas equation, is the equation of state of a hypothetical ideal gas. It is a good approximation of the behavior of many gases under many conditions, although it has several limitations. It was first stated by Benoît Paul Émile Clapeyron in 1834 as a combination of the empirical Boyle's law, Charles's law, Avogadro's law, and Gay-Lussac's law. The ideal gas law is often written in an empirical form:




P
V
=
n
R
T


{\displaystyle PV=nRT}
where



P


{\displaystyle P}
,



V


{\displaystyle V}
and



T


{\displaystyle T}
are the pressure, volume and temperature;



n


{\displaystyle n}
is the amount of substance; and



R


{\displaystyle R}
is the ideal gas constant. It is the same for all gases.
It can also be derived from the microscopic kinetic theory, as was achieved (apparently independently) by August Krönig in 1856 and Rudolf Clausius in 1857.

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  1. J

    Question about the derivation of the Ideal Gas Law

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  2. sliperyfrog

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  3. KDS4

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  4. marcophys

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  5. astrocytosis

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  6. Tardis Traveller

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  7. M

    I Ideal Gas Law - Real Life Question?

    Hi Guys and Gals, As I was pumping up a flat bike tyre, a weird thought occurred to me about the application of the ideal gas law. Once the tyre essentially finds its physical dimension limitations (i.e. is shaped like a bike tyre and no longer changing shapes) and starts putting in reasonable...
  8. S

    Why is 2L used as the distance in the derivation of 1/3nMc^2 = nRT?

    In the derivation the first step used F=Δmv/t and for t, they used t=2L/v where L is the distance between one end to the other end of the wall. But I don't understand why we use 2L as the distance. Isn't the force exerted by that molecule only for the very short period where the molecule is in...
  9. C

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  10. S

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  11. EliotBry

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    Homework Statement Problem from the book "Engines, Energy and Entropy", Page 55, question 7 has me stumped. It doesn't feel like their is sufficient information to work out the mass of the air. They've given us density (as seen in the picture, if the upload works) , which is mass over volume...
  12. M

    Fill Balloons Homework: Max # People for Bday Party Balloon

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  13. Z

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  14. V

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  15. ptownbro

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  16. RaulTheUCSCSlug

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  17. B

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  18. A

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    Homework Statement My problem is with the last line of the derivation. Usually, we take the rate of change of momentum (force) to be change of momentum divided by the impact time. But this slide of pp showed that the traveling time of the particle in the box is used but not the impact time. Why...
  19. 0

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  20. @PinkGeology

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  21. goonking

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  22. E

    Ideal Gas Law - Adding additional gas & additional question

    Hello, I know this has been fairly discussed to death, but I've had relative trouble finding a response that specifically addresses the n, in PV= nRT, the ideal gas law. Out of relatively common sense, by adding additional moles of gas, the pressure in the gas should increase as there are more...
  23. A

    Question about Ideal gas law and its application

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  24. E

    How Is Time Factored Into the Derivation of the Ideal Gas Law?

    Here is a screenshot from a page from a textbook that explains how to derive the ideal gas law: In the third bold line, I don't understand how "time" in force = (change of momentum)/(time) is equal to 2x/u (the time it takes for the particle to travel to the opposite face and back again) -- I...
  25. A

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  26. J

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  27. Z

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  28. T

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  29. K

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  30. I

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  31. D

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  32. J

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  33. T

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  34. B

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  35. B

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  36. G

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  37. C

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  38. A

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  39. M

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  40. Night-san

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  41. A

    MHB Ideal Gas Law: Pressure, Volume, & Temperature Changes

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  42. S

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  43. R

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  44. A

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  45. H

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  46. marellasunny

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  47. K

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  48. A

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  49. D

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  50. K

    Understanding Moles From Ideal Gas Law

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