Explain electrolysis, write half‑equations, predict products (including electro‑plating) and describe a hydrogen‑oxygen fuel cell.
Discuss enthalpy changes, activation energy, bond‑energy calculations and use reaction‑profile diagrams.
Identify factors affecting reaction rate, write reversible reactions, apply collision theory and Le Chatelier’s principle.
Describe properties of acids, bases and salts, use the pH scale and write neutralisation equations.
Recall periodic‑table trends, the characteristic properties of groups I, VII, transition metals and noble gases.
Explain metal properties, the reactivity series, extraction methods, alloy formation and corrosion prevention.
Discuss the chemistry of water, fertilisers, air pollutants and climate‑change mitigation.
Identify the main functional groups, name simple organic compounds and describe the formation of polymers, especially nylon (a polyamide) and PET (a polyester).
1. States of Matter (Core + Supplement)
Solids – fixed shape & volume; particles vibrate in fixed positions; usually high density.
Liquids – fixed volume only; particles slide past one another; moderate density.
Gases – no fixed shape or volume; particles move rapidly in all directions; low density.
Kinetic Particle Theory (KPT) – explains the differences between the states:
Particle size is the same in all three states.
Inter‑particle forces: strongest in solids, weaker in liquids, weakest in gases.
Particle energy increases from solid → liquid → gas (temperature‑dependent).
Diffusion & Effusion (Supplement)
Diffusion – mixing of gases (or liquids) due to random motion of particles. Rate ↑ with higher temperature and lower molecular mass.
Effusion – escape of gas molecules through a tiny hole. Graham’s law: \( \frac{r_1}{r_2}= \sqrt{\frac{M_2}{M_1}} \) (rate ∝ 1/√M).
Heating / Cooling Curves
Show temperature change vs. energy added or removed.
Flat sections correspond to phase changes (latent heat of fusion/vapourisation).
Gas Laws (Supplement)
PV = nRT (ideal‑gas equation). At constant T, P ∝ 1/V (Boyle’s law). At constant P, V ∝ T (Charles’s law).
2. Atoms, Elements & Compounds
2.1 Atomic Structure
Protons (+) and neutrons (neutral) in the nucleus; electrons (‑) in shells.
Atomic number (Z) = number of protons; mass number (A) = protons + neutrons.
Isotopes: same Z, different A (e.g., ¹²C, ¹³C, ¹⁴C).
Reaction stoichiometry: 2 Na + Cl₂ → 2 NaCl. Need 2 mol Na per 1 mol Cl₂. Required Na = 2 × 0.028 = 0.056 mol. We have 0.087 mol > 0.056 mol, so Cl₂ is limiting.
Maximum NaCl formed = 2 × 0.028 = 0.056 mol × 58.44 g mol⁻¹ ≈ 3.27 g.
4. Electrochemistry (Core + Supplement)
4.1 Electrolysis Basics
Electrolyte – molten or aqueous ionic compound that conducts electricity.
Two electrodes: anode (positive, oxidation) and cathode (negative, reduction).
Inert electrodes (e.g., Pt, C) do not take part in the reaction; active electrodes (e.g., Cu) can be dissolved or deposited.
4.2 Writing Half‑Equations
General steps:
Identify oxidation and reduction processes.
Write each as a separate ionic equation, balancing charge with electrons.
Combine to give the overall balanced equation.
Example – Electrolysis of Aqueous CuSO₄ (inert electrodes)
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