Answer:
The temperature is 30,92K
Explanation:
We use the formula PV=nRT. We convert the unit of pressure in kPa into atm.
101,325kPa----1atm
121kPa-------x=(121,3kPax 1 atm)/101,325kPa=1, 2 atm
PV=nRT---->T= (PV)/(RT)
T=(1,2 atm x 3L)/(1,42 mol x 0,082 l atm/K mol )= 30, 91721058 K