OCR A Level Chemistry A Paper 1 2025 Mark Scheme

Get the official OCR A-Level Chemistry A H432/01 Periodic Table, Elements and Physical Chemistry mark scheme from the June 2025 examination series. This examiner-approved PDF contains the exact mark allocations, calculation methods, indicative scientific points, level-of-response descriptors, examiner annotations, graph guidance, and assessment-objective breakdowns used during live Summer 2025 OCR marking.

This mark scheme provides detailed examiner guidance for questions covering Born–Haber cycles, ionisation-energy trends, entropy and Gibbs free energy calculations, Kp equilibrium systems, Arrhenius activation-energy graphs, heterogeneous catalysis, reaction orders and rate equations, buffer-solution calculations, electrode potentials, transition-metal complexes, stereoisomerism, and iodometric titration analysis involving copper(II) sulfate and iron(II) sulfate mixtures. It includes accepted alternative answers, error-carried-forward guidance, graph-marking tolerances, level-of-response criteria, significant-figure rules, equilibrium explanations, and OCR annotation conventions used by examiners in the live 2025 series. Pair it with the matching OCR H432/01 June 2025 question paper on markscheme.net for complete examiner-style revision and exam preparation. Updated for the 2025/2026 academic year, mobile-friendly, and instantly downloadable from markscheme.net.

This document is designed for OCR A-Level Chemistry A students preparing for the 2026 examination series, Year 13 learners studying Periodic Table, Elements and Physical Chemistry, retake students targeting A/A* grades, and home-schooled candidates seeking examiner-level insight into OCR marking expectations.

It is also essential for teachers, private tutors, revision-course providers, and parents supporting Chemistry revision at home. The mark scheme can be used for mock-exam grading, kinetics-answer verification, equilibrium-calculation checking, graph-analysis training, electrochemistry assessment, and identifying weaknesses in OCR Chemistry exam technique.