## Post Assessment PART 1B NUMBER 47

Phuong Tran 1G
Posts: 33
Joined: Sat Sep 14, 2019 12:16 am

### Post Assessment PART 1B NUMBER 47

47. The reaction 2 SO2 (g) + O2 (g) ⇌ 2 SO3 (g) occurs in a 1.00 L flask at 312 K and at equilibrium the concentrations are 0.075 mol.L-1 SO2 (g), 0.537 mol.L-1 O2 (g), and 0.925 mol.L-1 SO3 (g). Calculate their respective partial pressures at 312 K using R = 8.206 × 10-2 L.atm.K-1.mol-1.

A. Pso2 = 1.2 atm; Po2 = 1.7 atm; Pso3 = 2.7 atm

B. Pso2 = 1.92 atm; Po2 = 13.7 atm; Pso3 = 23.7 atm

C. Pso2 = 1.92 atm; Po2 = 3.7 atm; Pso3 = 21.7 atm

D. Pso2 = 1.92 atm; Po2 = 13.7 atm; Pso3 = 2.7 atm

E. None of the above

Is the answer none of the above? I keep getting different values for all of the them no matter how many times I do it. Like for Pso2, I got .0029 bc (.075)/((312)(8.206*10^-2))

Jason Wu 1E
Posts: 101
Joined: Thu Jul 25, 2019 12:15 am

### Re: Post Assessment PART 1B NUMBER 47

The answer should be B. In this question, you are simply asked to convert concentrations at equilibrium to partial pressures at equilibrium. To do so, the partial pressure always equals the concentration in moles per liter times the R value times the temperature in Kelvin. Doing all the steps above for each compound present leads you to B.