Answer:
The total pressure is 1.616 atm
Explanation:
First of all we say:
In a closed system, sum of partial pressures is the value for the total pressure.
In our system, we have gas A and B
Total pressure without the third gas is = 0.373 atm + 0.650 atm = 1.023 atm
As we add a third gas, with no change in volume or T°, let's find out by the Ideal Gases Law, its pressure:
P . V = n . R . T
P = ( n . R . T) / V
P = (0.220 mol . 0.082 . (273 + 21°C)) / 8.95L = 0.593 atm
273 + 21°C → Absolute value of T°
Let's sum the partial pressures, then:
0.373 atm + 0.650 atm + 0.593 atm = 1.616 atm.
It's ok to say that the total pressure was increased, because we have more gas now.
