At 900.0 K, the equilibrium constant (Kp) for the following reaction is 0.345.
2SO₂(g) + O₂(g) ⇌ 2SO₃(g)
At equilibrium, the partial pressure of SO₂ is 29.5 atm and that of O₂ is 13.4 atm. The partial pressure of SO₃ at equilibrium is ________ atm.
A. 136
B. 5.44 × 10⁻³
C. 8.72 × 10⁻⁴
D. 33.9
E. 63.4