Combined Science (A) J250,10 Higher June 2022, OCR GCSE Past Papers with Mark Schemes

1. Reaction Rates and Experimental Methods – Investigating magnesium and acid reaction rates, gas collection techniques, and calculating reaction speed using tangents.

2. Greenhouse Effect and Climate Change – Infrared radiation absorption, atmospheric CO₂ levels, and historical changes in Earth′s atmosphere.

3. Fractional Distillation and Hydrocarbons – Separation of crude oil fractions, alkane identification, and improving distillation techniques for low boiling point fractions.

4. Electrolysis and Industrial Processes – Sodium extraction from molten NaCl, evaluation of cost factors, and writing half-equations for electrolysis reactions.

5. Le Chatelier’s Principle and Equilibrium – Temperature and pressure effects on ethanol production, balancing industrial reaction conditions, and energy considerations.

6. Group 0 and Group 7 Elements – Trends in noble gas reactivity, fluorine’s high reactivity, and intermolecular forces affecting halogen boiling points.