Work through the list without notes. If you cannot do a statement, follow its link, then come back. Guide = study guide; Practice = practice questions.
Understanding
- I can explain that a stress takes a system out of equilibrium by making Q different from K. (Guide: “From a rule of thumb to a reason”)
- I can state which way a reaction goes when Q < K and when Q > K, and why. (Guide: Figure 1; Practice Q1)
- I can say which stresses change Q and which change K. (Guide: stress table; Practice Q2)
- I can explain why heating a rigid flask leaves Q unchanged at that instant but changes K. (Guide: Worked example 3; Practice Q6(b))
Calculation
- I can calculate Q after a species is added or removed, and compare it with K. (Guide: Worked example 1; Practice Q7(a))
- I can calculate Q for a mixture that is not at equilibrium, including terms with powers. (Practice Q5)
- I can find the new Q after a change in gas volume, using partial pressures or the factor rule. (Guide: Worked example 2; Practice Q4)
- I can find the new Q after diluting a solution. (Guide: factor rule; Practice Q3)
- I can use one given concentration at a new equilibrium to find the others and check that Q = K. (Practice Q7(b))
- I can find a new equilibrium mixture when the equation gives a perfect square. (Guide: Worked example 3; Practice Q6(c))
Reasoning
- I can deduce the sign of ΔH from how K changes with temperature. (Practice Q6(a))
- I can explain why the new equilibrium concentrations differ from the old ones even though Q returns to the same K. (Guide: Worked example 1; Practice Q7(c))
All ticked? Move on to Topic 7.11, Introduction to Solubility Equilibria, or return to the course roadmap.