With temperature you must ALWAYS be in Kelvin. Change to Kelvin (K)!!!!!! Like with pressure, volume can stay in mLs as long as you are not using PV = nRT. Again, because of the units of R.
And for an ideal gas, would the volume always be 22.41 L?
Sorry for all the questions!
Only when the conditions are at STP where P = 1 atm and T is 273K.
Only when PV = nRT is used. Because R has units of L ATM/mole K
You must convert pressure to atm when PV = nRT is used because R has units of L-atm/mole-K. In the other cases you do not need to convert because the units will cancel as long as the pressure values share the same unit.
chemdoctor 
So do you only have to convert the pressure to Atm when it’s an ideal gas law problem?
And also with volume (mL-L) and temperature (C-K)?
With temperature you must ALWAYS be in Kelvin. Change to Kelvin (K)!!!!!! Like with pressure, volume can stay in mLs as long as you are not using PV = nRT. Again, because of the units of R.
And for an ideal gas, would the volume always be 22.41 L?
Sorry for all the questions!
Only when the conditions are at STP where P = 1 atm and T is 273K.
Only when PV = nRT is used. Because R has units of L ATM/mole K
You must convert pressure to atm when PV = nRT is used because R has units of L-atm/mole-K. In the other cases you do not need to convert because the units will cancel as long as the pressure values share the same unit.