IB Chemistry 1.4.1 (HL) Entropy (S) Questions
IB Chemistry 1.4.1 (HL) Entropy (S) Questions
Predict when entropy increases or decreases from states and particle counts, then calculate ΔS°r from tabulated S° values with correct signs and units.
How this is tested
- predict the sign or relative size of ΔS from changes such as NH3(g) + HCl(g) → NH4Cl(s) or 2 NO2(g) → N2O4(g)
- explain a negative entropy change using fewer gas particles or gas forming a liquid product
- calculate ΔS°r from S° data for reactions such as phosgene formation or esterification, with units of J K−1 mol−1