posted by Stephanie on .
A piston pump containing 2 liters of nitrogen gas at 3000 psia (absolute) pressure empties its entire contents into a 10 liter pressure container. Before the transfer of gas the 10 liter container already contained nitrogen gas at 100 psia (absolute) pressure. Assuming nitrogen behaves as an ideal gas, and assuming the temperature is the same throughout what is the final pressure in the container?
V, R and T constant for 10 liter container
P2 /N2 = P1 /N1
now work on how many molecules
10 liters 100 psi:
n = pV/RT = 100*10/RT = 1000/RT = N1
2 liters at 3000 psi
n = 3000*2/RT = 6000/RT
so total n at the end in the 10 liters is = 7000/RT = N2
Now do P2/N2 =P1/N1 for the 100 liters
P2/7000 = 100/1000
P2 = 700 psi