Answer:
At equilibrium, Kc = 0.058
Step-by-step explanation:
Step 1: Data given
Mol SO3 = 12.6
Volume = 4.0 L
At equilibrium we have:
3.4 mol of SO2
Step 2: The balanced equation
2SO3(g) + ⇆ 2SO2(g) + O2(g)
Step 3: ICE-chart
The initial number of moles are:
SO3: 12.6 moles
SO2 : 0 mol
O2: 0 mol
There will react:
SO3: -2x
SO2: +2x
O2: +x
The number of moles at the equilibrium are:
SO3: 12.6 - 2x
SO2: 2x = 3.4 mol
O2: x
Since at the equilibrium, we have 2x = 3.4 mol. x = 1.7 mol
This means at the equilibrium we have 1.7 mol of O2 and 12.6 -3.4 = 9.2 mol of SO3
Step 4: Calculate the equilibrium constant Kc
Kc = [3.4/4]² *[1.7/4] / [9.2/4]²
Kc = 0.058
At equilibrium, Kc = 0.058