3cReversible reactions and equilibria

Syllabus objectives

• 3.17know that some reactions are reversible and this is indicated by the symbol ⇌ in equations
• 3.18describe reversible reactions such as the dehydration of hydrated copper(II) sulfate and the effect of heat on ammonium chloride
• 3.19know that a reversible reaction can reach dynamic equilibrium in a sealed containerSeparate Chemistry only
• 3.20know that the characteristics of a reaction at dynamic equilibrium are: • the forward and reverse reactions occur at the same rate • the concentrations of reactants and products remain constant.Separate Chemistry only
• 3.21understand why a catalyst does not affect the position of equilibrium in a reversible reactionSeparate Chemistry only
• 3.22know the effect of changing either temperature or pressure on the position of equilibrium in a reversible reaction: • an increase (or decrease) in temperature shifts the position of equilibrium in the direction of the endothermic (or exothermic) reaction • an increase (or decrease) in pressure shifts the position of equilibrium in the direction that produces fewer (or more) moles of gas References to Le Chatelier's principle are not requiredSeparate Chemistry only