Answer:
The correct answer is 0.047 mol/L
Explanation:
The atmospheric air is a mixture of gases. We can assume an ideal behavior of the gas and use the ideal gas equation:
PV= nRT
where P is the pressure, V is the volume, n is the number of moles, R is a constant (0.082 L.atm/K.mol) and T is the temperature in K.
We have to first convert the pressure from Torr to atm:
760 Torr= 1 atm
⇒ 718 Torr x 1 atm/760 Torr = 0.945 atm
Then, we convert the temperature from ºC to K:
0ºC = 273 K
⇒ -29ºC+273= 244 K
Finally, we introduce the data in the equation and calculate de densitiy, which is the moles per liters of gas (n/V):
PV = nRT
n/V= P/RT
n/V = (0.945 atm)/(0.082 L.atm/K.mol x 244 K) = 0.047 mol/L