Sulfur dioxide is converted to sulfur trioxide according to 2 , SO_2(g) + O_2(g) ; ;2…
CHEMISTRY · Multi-part · A Level · Chemistry · Chemical equilibria (Le Chatelier’s principle and Kc) · Chemical equilibria (Le Chatelier’s principle and Kc)
Problem
Sulfur dioxide is converted to sulfur trioxide according to
2SO2(g)+O2(g)⇌2SO3(g)
A sealed 1.25 L reaction vessel at fixed temperature is examined twice. In both snapshots, 20 green spheres (Ne) are present as an inert gas.
Snapshot 1: 80 SO₂ molecules, 40 O₂ molecules, 160 SO₃ molecules
Snapshot 2: 50 SO₂ molecules, 25 O₂ molecules, 110 SO₃ molecules
Each particle once again represents 5.00×1020 molecules. NA=6.022×1023mol−1.
(a) Write the equilibrium-constant expression Kc for the reaction.
(b) Calculate Kc from the data in Snapshot 1. Clearly show your reasoning.
(c) Calculate Kc from the data in Snapshot 2.
(d) Evaluate whether the two snapshots are consistent with the system being at equilibrium at the stated temperature. Support your answer with quantitative evidence and chemical reasoning.