Units
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Units
When we are calculating using the ideal gas law, should we put the temperature in Kelvins or in Celsius?
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Re: Units
Yes, you would put temperature in Kelvin. Usually when doing calculations, Kelvin is the unit that should be used.
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Re: Units
The units should be in Kelvin as the universal gas constant, R is in Kelvin. To find convert from Celsius to Kelvin just add 273.15.
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Re: Units
Yeah use K. Whenever you are confused as to which unit to use, look at the constant values in the equation and use the units that will cancel out with them. In this case of PV = nRT, R uses K.
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Re: Units
Kelvin should be used when calculating these type of problems due to the fact that 0 Kelvin is absolute 0.
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Re: Units
Yes, as people said before you should always use Kelvin. It is also important to note that you must match pressure units for whatever R constant you are using or else your answer will be incorrect. You can also convert to whatever units the question asks before plugging in your values to PV=nRT.
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Re: Units
You use Kelvin since R is in terms of Kelvin. If you were given a different temperature unit, you would have to convert it to Kelvin.
Example, 52 degrees Celsius to K.
C+273.15=K
52+273.15=300.15K
Example, 52 degrees Celsius to K.
C+273.15=K
52+273.15=300.15K
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Re: Units
The temperature is always plugged in as Kelvin. If the question concern the change in temperature in celsius, you calculate using kelvins and convert to celsius in the last step.
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Re: Units
Use Kelvin.
The Gas Constant is in Kelvin so we have to use the same measurement for temperature.
To get Kelvin, just add 273.15 to your Celcius measurement.
The Gas Constant is in Kelvin so we have to use the same measurement for temperature.
To get Kelvin, just add 273.15 to your Celcius measurement.
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Re: Units
Always use Kelvin! If a problem states a temperature in Celsius (this is very common) or Fahrenheit, convert it to Kelvin.
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