Answer:
The correct answer is 5.0 L
Explanation:
STP are defined as T=273 K and P= 1 atm
By using the ideal gas equation, we can calculate the number of moles (n) of the gas at a volume V=2.5 L:
PV= nRT
⇒n= (PV)/(RT) =(1 atm x 2,5 L)/(0.082 L.atm/K.mol x 273 K)= 0.112 mol
For a sample of argon gas, with the same number of moles (0.112 mol) but twice the temperature (T = 273 K x 2= 546 K):
V= (nRT)/P = (0.112 mol x 0.082 L.atm/K.mol x 546 K)/1 atm = 5.0 L
That is consistent with the fact that when a gas is heated, it expanses. So, if the temperature increases twice, the volume also increases twice.
