OCR AS Chemistry Topical Download Past Papers from OCR site here 2021-20 Acid–base reactions AlcoholsAmount of substance Analytical techniques (IR and MS)Atoms, compounds, molecules and equationsChemical equilibrium (qualitative)Electrons, bonding and structureEnthalpy changes HydrocarbonsReaction rates (qualitative)The halogensThe periodic table and periodicity Topical Solutions coming soon
