Question

a pressurized tank for diving is filled with 4.0L gas which constitutes of 50g of O2 and 150g of N2 . Calculate the partial pressure for each gas and total gas pressure.

Answer 1

moles of O2 = 50 / 32 = 1.56

moles of N2 = 150 / 28 = 5.36

total moles = 5.36 + 1.56 = 6.92

mole fraction of O2 = moles of O2 / total moles = 1.56 / 6.92 = 0.225

mole fraction of N2 = 0.775

V = 4.0 L

T = 298 K

P V = n RT

P x 4 = 6.92 x 0.0821 x 298

P = 42.33 atm

total pressure =42.33 atm

partial pressure of O2 = mole fraction x total pressure

= 0.225 x 42.33

= 9.52 atm

partial pressure of O2 =9.52 atm

partial pressure of N2 = 0.775 x 42.33

partial pressure of N2 = 32.80 atm