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 “thermodynamically favoured” (ΔG° < 0) means products are favoured at equilibrium (K > 1) under standard conditions. (Guide: “Two ways of saying products are favoured”; Practice Q1)
- I can state which range of K goes with a negative, zero and positive ΔG°. (Guide: sign table; Practice Q1)
- I can explain why a positive ΔG° still allows some product to form. (Practice Q6)
- I can explain why a favoured reaction is not necessarily fast. (Guide: “Common misconceptions”)
Calculation
- I can calculate K from ΔG° at a given temperature, converting kJ to J and using e, not 10. (Guide: Worked example 1; Practice Q2)
- I can calculate ΔG° from K using ln, and check that the sign of ΔG° matches the size of K. (Guide: Worked example 2; Practice Q4)
- I can find ΔG° and K at a new temperature from ΔH° and ΔS°, and find the temperature at which K = 1. (Guide: Worked example 3; Practice Q5)
- I can use a value of K to find an equilibrium concentration for a simple reaction. (Practice Q6)
Reasoning
- I can estimate whether K is close to 1 or far from 1 by comparing ΔG° with RT (about 2.5 kJ mol⁻¹ at 298 K). (Guide: “Estimating K”; Practice Q3)
- I can use the “5.7 kJ mol⁻¹ per factor of 10” rule at 298 K to estimate K or a ratio of K values. (Guide: Figure 1; Practice Q3, Q7)
- I can explain why raising the temperature increases or decreases K, using the signs of ΔH° and ΔS°. (Practice Q5)
- I can evaluate a claim about favourability or product formation with a calculation as evidence. (Practice Q6, Q7)
All ticked? Move on to Topic 9.6, Free Energy of Dissolution, or return to the course roadmap.