Step1 Pressure due to N2 = 2x.0821 x300/4.0 =12.315 atm Step2 Pressure due to O2 = 4 x.0821x300/4.0 =24.630 atm Step3 Pressure due to Cl2 =1x.0821x300/4.0 = 6.1575 atm Step4 Total pressure = 43.1025 atm Solution Step1 Pressure due to N2 = 2x.0821 x300/4.0 =12.315 atm Step2 Pressure due to O2 = 4 x.0821x300/4.0 =24.630 atm Step3 Pressure due to Cl2 =1x.0821x300/4.0 = 6.1575 atm Step4 Total pressure = 43.1025 atm.