A closed container of 10 L contains 2 moles of gas A and 3 moles of gas B at 27°C. If the total pressure exerted by the mixture is 5 atm, what is the partial pressure of gas B?
Correct: B
According to Dalton's Law of Partial Pressures, the partial pressure of a gas in a mixture is equal to its mole fraction multiplied by the total pressure.
Total moles of gas = Moles of A + Moles of B = 2 moles + 3 moles = 5 moles.
Mole fraction of gas B (XB) = Moles of B / Total moles = 3 moles / 5 moles = 0.6.
Partial pressure of gas B (PB) = XB × Total pressure (P_total) = 0.6 × 5 atm = 3 atm.