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    Do I need specific units for P, and V for these laws?
    P1V1/T1=P2V2/T2 or PV=nRT
    I know it's a bit silly but I forgot and I'm not quite sure but I know T is in Kelvin.


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    (Original post by Expialidocious)
    Do I need specific units for P, and V for these laws?
    P1V1/T1=P2V2/T2 or PV=nRT
    I know it's a bit silly but I forgot and I'm not quite sure but I know T is in Kelvin.


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    Well usually you'd use SI units i.e. Pa and m3

    For the equations above, i'd advise using the units ; P -> Pa
    V -> m3
    T -> K
    n -> mol
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    But is it essential to convert like atm to Pa? Or is it alright if I'd use atm for the combined law?


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    (Original post by ZakRob)
    Well usually you'd use SI units i.e. Pa and Dm

    For the equations above, i'd advise using the units ; P -> Pa V -> Dm-3 T -> K n -> mol
    Decimetres are not SI units. Metres are. Units of volume are m3
    (Original post by Expialidocious)
    But is it essential to convert like atm to Pa? Or is it alright if I'd use atm for the combined law?
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    It is unfortunately essential 1atm =100,000 Pa
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    (Original post by joostan)
    Decimetres are not SI units. Metres are. Units of volume are m3

    It is unfortunately essential 1atm =100,000 Pa
    Yeah that's what I meant m3 for volume, I don't why I put dm-3. I've changed it now anyway.
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    (Original post by ZakRob)
    Yeah that's what I meant m3 for volume, I don't why I put dm-3. I've changed it now anyway.
    Concentration's the funny one for chem. No worries
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    I feel quite stupid for asking this again but for Boyle's and Charles' Law, I'd need to convert it to STP right? I'm so so sorry


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    (Original post by Expialidocious)
    I feel quite stupid for asking this again but for Boyle's and Charles' Law, I'd need to convert it to STP right? I'm so so sorry


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    No it does not need to be STP. Converting to STP is impossible without changing the reaction. STP is standard temperature and pressure. You do however need SI units again
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    (Original post by joostan)
    Decimetres are not SI units. Metres are. Units of volume are m3

    It is unfortunately essential 1atm =100,000 Pa
    1 atmospheric pressure is just slightly higher than 1 bar = 10^5 Pa.
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    (Original post by shengoc)
    1 atmospheric pressure is just slightly higher than 1 bar = 10^5 Pa.
    Yeah, but 101325 is so much messier
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    (Original post by joostan)
    Yeah, but 101325 is so much messier
    you are fortunate i am not a mathematician to argue the "power" of the equal sign. LOL
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    (Original post by shengoc)
    you are fortunate i am not a mathematician to argue the "power" of the equal sign. LOL
    say wha?
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    For the combined gas law you need pressure in Pa, temperature in K, volume in m3. For the ideal gas law, you can use whatever units you like - so long as your R compensates!
 
 
 
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