Turn on thread page Beta
    • Thread Starter
    Offline

    9
    ReputationRep:
    Okay so when I workout enthalphy change of combustion , I’m given the temperature change in Celsius but I always change it to kelvin , is that okay? Or am I suppose to leave the Celsius ? In my worksheet it says temperature change (K)
    Offline

    9
    ReputationRep:
    I suspect you need to use the temperature CHANGE for you calculation of the amount of energy obtained in this experiment. Presumably you are using the equation q = mcΔT ?

    If you only need the temperature rise, the change in temperature then you can use Celcius. Each degree Celsius is the same size as a degree Kelvin, so a 10°C rise is the same as a 10K rise.

    When you come to equations where you use a specific temperature you do need to use Kelvin every time. I don't think you will need to for this question.
    • Thread Starter
    Offline

    9
    ReputationRep:
    (Original post by TutorsChemistry)
    I suspect you need to use the temperature CHANGE for you calculation of the amount of energy obtained in this experiment. Presumably you are using the equation q = mcΔT ?

    If you only need the temperature rise, the change in temperature then you can use Celcius. Each degree Celsius is the same size as a degree Kelvin, so a 10°C rise is the same as a 10K rise.

    When you come to equations where you use a specific temperature you do need to use Kelvin every time. I don't think you will need to for this question.
    So what about a question where it says it has been raised to 8 Celsius ? I always changed it to kelvin . Is that okay ? If not why?
    Offline

    9
    ReputationRep:
    (Original post by KillerCosine)
    So what about a question where it says it has been raised to 8 Celsius ? I always changed it to kelvin . Is that okay ? If not why?
    What was the temperature change? What temperature did you start with?

    It's not at all wrong to have converted it, it is just unnecessary when calculating temperature CHANGE.
    • Thread Starter
    Offline

    9
    ReputationRep:
    (Original post by TutorsChemistry)
    What was the temperature change? What temperature did you start with?

    It's not at all wrong to have converted it, it is just unnecessary when calculating temperature CHANGE.
    The question just tells me it has been raised to 8 Celsius , no information for the starting temp just that it has been raised by 8 Celsius . What then I assumed that it is better to turn it into K 281K.


    PS now that I think of it temperature change of 8 is the same as if you compared it with kelvin . Right?


    Btw thank you
    Offline

    10
    ReputationRep:
    (Original post by KillerCosine)
    ...raised to 8 Celsius...

    ...raised by 8 Celsius...
    Well, which is it

    I suspect it was raised by 8 degrees Celsius, this is the same as a rise of 8Kelvin

    When taking differences using kelvin or Celsius doesnt matter because the units are the same size.

    If you are interested in absolute temperature, best to use Kelvin.
 
 
 
Poll
Do you think parents should charge rent?

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.