All competitions
UK Chemistry Olympiad Round 1
UKChO, run by the Royal Society of Chemistry, is a written paper for Year 13 students, sat at school in late January.
It expects A-Level chemistry and goes beyond it: entropy and Gibbs energy, rate laws and half-lives, the Nernst equation, and organic chemistry with reagents you probably have not have met. The 30 best scorers are invited to Round 2.
How to prepare here
- Approach mode asks you to plan a route before any numbers, which is most of the work in a Round 1 calculation.
- Drill reagents with Classify so the organic questions are about thinking, not recall.
- Exam mode times each question; Round 1 rewards working quickly and accurately.
Conventions
- 3 significant figures unless the question says otherwise.
- Units: SI; concentrations in mol dm⁻³.
- Constants as on the data sheet: R = 8.314, NA = 6.022 × 10²³, F = 96485.
UKChO Round 1 question types (34)
- ΔG from ΔH and ΔS
- K from ΔG°
- ΔG° from K
- K from ΔH° and ΔS°
- First order: concentration after time t
- Activation energy from two rate constants
- Second-order half-life
- Radioactive decay: elapsed time
- pH of a weak acid
- Buffer pH (Henderson–Hasselbalch)
- Moles of an ideal gas
- ΔG° from E°
- Hess's law from enthalpies of formation
- ΔH from a bomb-calorimeter ΔU
- Kp from Kc
- Solubility from Ksp
- pH of a weak base
- Mass deposited by electrolysis
- E°cell from reduction potentials
- Concentration from absorbance
- Wavelength to break a bond
- Oxygen content from combustion analysis
- Iron in a tablet by permanganate titration
- Copper(II) by iodometric titration
- Ksp from a solubility in g dm⁻³
- Solubility with a common ion
- Time for a second-order reaction to reach a concentration
- Rate constant from total pressure
- Equilibrium constant from E°cell
- Electrode potential away from standard conditions
- Enthalpy of solution from a thermodynamic cycle
- Methanol synthesis: K from tabulated data
- pH of benzoic acid from a weighed sample
- H₂ + I₂ ⇌ 2HI: equilibrium amounts
Book pages for this level
Plus 47 reagents to drill in the reagent trainer.