Chemistry lessons, practice and exam preparation
Understand chemistry. Practise what matters. Syllabus-aligned learning for Secondary G1 to G3 Science and Chemistry, current G3 Pure Chemistry K324, legacy GCE O-Level Chemistry 6092, H1 8873, H2 9476, and H3 9813.
Maxwell–Boltzmann energy distributions at two temperatures A lower-temperature curve has a taller peak at lower energy. A higher-temperature curve is lower, broader, and extends farther right. An activation-energy threshold marks the particles energetic enough to react. A second, lower threshold shows the effect of a catalyst. Eₐ uncatalysed lower Eₐ with catalyst lower temperature higher temperature larger fraction with E ≥ Eₐ Particle energy, E Fraction of particles per unit energy Schematic: each curve has the same total area for the same number of particles. Temperature redistributes particle energies; a catalyst lowers the activation-energy threshold. Secondary G1–G3
Choose the Science or Chemistry pathway that matches your course. G1 Science family pathway G2 Science (Chemistry) G3 Combined Science Chemistry G3 Pure Chemistry Explore Secondary G3 Pure Chemistry K324 / legacy O-Level 6092
Build complete Chemistry foundations and exam technique. Ordered topic lessons MCQ and structured practice Paper 3 practical support Revision plans and mock papers Explore O-Level A-Level H1 / H2 / H3
Choose H1, H2 or H3 at the depth required for your course. H1 Chemistry (8873) H2 Chemistry (9476) H3 Chemistry (9813, 2027) H3 is taken alongside H2 in the same examination year Explore A-Level G2 Science (Chemistry) G3 Science (Chemistry) G3 Pure Chemistry (K324) GCE O Level Chemistry (6092) H1 Chemistry (8873) H2 Chemistry (9476) H3 Chemistry (9813) Featured concept
From particle energy to exam marks Connect collision theory, activation energy, temperature, and catalysts at the depth your course requires.
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