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Units of the universal gas constant - Jk-1mol-1 Watch

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    why mol^-1 ?

    PV=nRT

    re-arranging to make R the subject, you get R = PV/nT.
    In terms of units:
    P*V = nm = J
    PV/T gives JK^-1
    And PV/Tn gives JK^-1mol^-1.

    So this implies that the number of moles has units - moles.
    I thought it wouldnt as it just seems like quantity/number to mee

    hmmm
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    It just depends whether you are doing units per mole or not:

    PV = RT (use 287 for air) OR PV = nRT (use 8.314)

    Both are equally valid but it depends what the question is asking.
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    I suppose as a unit, it is slightly strange, as it is just referring to a fixed number of molecules/atoms/ions/etc.
    However it is much more convenient to refer to 0.8mol, than 0.8x6.02214x10^23 or whatever.
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    (Original post by Van_der_Waals)
    I suppose as a unit, it is slightly strange, as it is just referring to a fixed number of molecules/atoms/ions/etc.
    However it is much more convenient to refer to 0.8mol, than 0.8x6.02214x10^23 or whatever.
    mmm yeh, but when u express the equation as PV=NkT, where k is boltzman constant, its units are Jk^-1, like you dont say x joules per kelvin per molecule, whereas with R you are saying x joules per kelvin per mole... lol
 
 
 
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