Inquiry question: What factors affect equilibrium and how?
investigate the effects of temperature, concentration, volume and/or pressure on a system at equilibrium and explain how Le Chatelier’s principle can be used to predict such effects, for example:
heating cobalt(II) chloride hydrate
interaction between nitrogen dioxide and dinitrogen tetroxide
iron(III) thiocyanate and varying concentration of ions
explain the overall observations about equilibrium in terms of the collision theory
examine how activation energy and heat of reaction affect the position of equilibrium
Calculating the Equilibrium Constant (Keq)
Inquiry question: How can the position of equilibrium be described and what does the equilibrium constant represent?
deduce the equilibrium expression (in terms of Keq) for homogeneous reactions occurring in solution
perform calculations to find the value of Keq and concentrations of substances within an equilibrium system, and use these values to make predictions on the direction in which a reaction may proceed
qualitatively analyse the effect of temperature on the value of Keq
conduct an investigation to determine Keq of a chemical equilibrium system, for example:
Keq of the iron(III) thiocyanate equilibrium
explore the use of Keq for different types of chemical reactions, including but not limited to:
dissociation of ionic solutions
dissociation of acids and bases
Solution Equilibria
Inquiry question: How does solubility relate to chemical equilibrium?
describe and analyse the processes involved in the dissolution of ionic compounds in water
investigate the use of solubility equilibria by Aboriginal and Torres Strait Islander Peoples when removing toxicity from foods, for example:
toxins in cycad fruit
conduct an investigation to determine solubility rules, and predict and analyse the composition of substances when two ionic solutions are mixed, for example:
potassium chloride and silver nitrate
potassium iodide and lead nitrate
sodium sulfate and barium nitrate
derive equilibrium expressions for saturated solutions in terms of Ksp and calculate the solubility of an ionic substance from its Ksp value
predict the formation of a precipitate given the standard reference values for Ksp