Hey there! Sign in to join this conversationNew here? Join for free
    • Thread Starter
    Offline

    3
    ReputationRep:
    How is the ideal gas equation a thing when each individual equation that's combined has it's own rules.

    For example: Pressure is inversely proportional to volume at constant temperature. Then pressure is directly proportional to temperature when volume is constant.

    How can you combine these things when the conditions aren't the same for each equation?

    The Pressure law states that volume is constant and Boyles law states that temperature is constant. There are different conditions because volume isn't constant for Boyles law. I don't get how you can combine them if they aren't true for each others conditions. Can anyone help?
    Offline

    5
    ReputationRep:
    (Original post by Squishy•)
    How is the ideal gas equation a thing when each individual equation that's combined has it's own rules.

    For example: Pressure is inversely proportional to volume at constant temperature. Then pressure is directly proportional to temperature when volume is constant.

    How can you combine these things when the conditions aren't the same for each equation?

    The Pressure law states that volume is constant and Boyles law states that temperature is constant. There are different conditions because volume isn't constant for Boyles law. I don't get how you can combine them if they aren't true for each others conditions. Can anyone help?
    First of all, I am assuming that you are referring to the combined gas law PV/T = constant.

    As you already know, V/T = constant. This means that Vx/T1 = V2/T2

    (where x is just a symbol indicating that Vx is different than V2 or V1)

    PV = constant, so P1V1 = P2Vx

    Solve for Vx in these two equations :

    Equation 1: Vx = V2T1/T2

    Substitute Vx in equation 2:

    P1V1 = P2 * V2T1/T2

    This gives us the combined gas law P1V1/T1 = P2V2/T2
 
 
 
  • See more of what you like on The Student Room

    You can personalise what you see on TSR. Tell us a little about yourself to get started.

  • Poll
    Has a teacher ever helped you cheat?
  • See more of what you like on The Student Room

    You can personalise what you see on TSR. Tell us a little about yourself to get started.

  • The Student Room, Get Revising and Marked by Teachers are trading names of The Student Room Group Ltd.

    Register Number: 04666380 (England and Wales), VAT No. 806 8067 22 Registered Office: International House, Queens Road, Brighton, BN1 3XE

    Write a reply...
    Reply
    Hide
    Reputation gems: You get these gems as you gain rep from other members for making good contributions and giving helpful advice.