CHEMISTRY · Single correct · A Level · Chemistry · Chemical equilibria (Le Chatelier’s principle and Kc) · Chemical equilibria (Le Chatelier’s principle and Kc)
Problem
For the gaseous reaction 2NO2(g)⇌2NO(g)+O2(g) at 298 K, the equilibrium constant is Kp=1.2×10−5. Which of the following best describes the composition of the equilibrium mixture under these conditions?
(a) The reaction proceeds essentially to completion, leaving very little NO2 unreacted.
(b) Reactants and products are present in comparable, appreciable amounts at equilibrium.
(c) The mixture contains almost exclusively reactants, with only trace amounts of products present.
(d) No prediction about the equilibrium composition can be made without knowing the initial partial pressures.