A-level CHEMISTRY Paper 1 Inorganic and Physical Chemistry

Answer all questions in the spaces provided. box This question is about equilibria. 0 1 . 1 Give two features of a reaction in dynamic equilibrium. [2 marks] Feature 1 Feature 2 . A gas-phase reaction is at equilibrium. When the pressure is increased the yield of product decreases. State what can be deduced about the chemical equation for this equilibrium. [1 mark] Question 1 continues on the next page Turn over ► . Carbon monoxide and hydrogen react to form methanol. CO(g) + 2 H2(g) ⇌ CH3OH(g) 0.430 mol of carbon monoxide is mixed with 0.860 mol of hydrogen. At equilibrium, the total pressure in the flask is 250 kPa and the mixture contains 0.110 mol of methanol. Calculate the amount, in moles, of carbon monoxide present at equilibrium. Calculate the partial pressure, in kPa, of carbon monoxide in this equilibrium mixture. [3 marks] box