ChemistryQ&A by dot point

Electrolysis of molten and aqueous compounds, the movement of ions to the electrodes, predicting the products at the cathode and anode, half equations at the electrodes, and the extraction of reactive metals.

Exothermic and endothermic reactions and their uses, reaction profiles, activation energy, and calculating the overall energy change from bond energies.

Word and balanced symbol equations, conservation of mass, balancing equations, ionic equations, and explaining apparent mass changes in open systems.

Oxidation and reduction in terms of oxygen and electrons, redox reactions, oxidising and reducing agents, and writing half equations for the loss and gain of electrons.

Relative formula mass, the mole and the Avogadro constant, calculating moles from mass, using mole ratios to find reacting masses, limiting reactants, and percentage yield.

The reactions of acids with metals, bases and carbonates, neutralisation, salts, the pH scale, strong and weak acids, and making soluble salts.

Covalent bonding as shared pairs of electrons between non-metals, dot and cross diagrams for simple molecules, simple molecular substances, and giant covalent structures such as diamond, graphite and silicon dioxide.

Ionic bonding as the transfer of electrons between metals and non-metals, the formation of positive and negative ions, dot and cross diagrams, ionic formulae, and the giant ionic lattice.

Metallic bonding as a lattice of positive ions in a sea of delocalised electrons, the link to the properties of metals (conduction, malleability, high melting points), and why alloys are harder than pure metals.

Nanoparticles, coarse and fine particles, the high surface area to volume ratio of nanoparticles and its consequences, uses and risks of nanoparticles, and the state symbols used in equations.

Pure substances, mixtures and formulations, and the techniques for separating mixtures: filtration, crystallisation, simple and fractional distillation, and paper chromatography with Rf values.

Relating bonding and structure to the properties of substances: melting and boiling points, electrical conductivity and state, across ionic, simple molecular, giant covalent and metallic substances, and the limitations of bonding models.

Complete and incomplete combustion of fuels, the formation of carbon dioxide, carbon monoxide, sulfur dioxide, oxides of nitrogen and particulates, and the effects of these pollutants.

Crude oil as a mixture of hydrocarbons, alkanes and their general formula, the fractional distillation of crude oil, the uses of the fractions, and the cracking of long-chain hydrocarbons.

The Haber process for making ammonia, the compromise conditions of temperature and pressure, the use of an iron catalyst and recycling, and the use and importance of NPK fertilisers.

Life cycle assessment (LCA) and its stages, the limitations of LCAs, and the advantages and disadvantages of recycling and reusing materials including metals.

The composition of the atmosphere, how it evolved over time, the greenhouse gases and the greenhouse effect, and the link between human activity, climate change and the carbon footprint.

Producing potable water by sedimentation, filtration and sterilisation, desalination by distillation and reverse osmosis, treating waste water, and the sustainable extraction of metals by phytomining and bioleaching.

Catalysts and how they lower the activation energy, enzymes as biological catalysts, the effect of catalysts on reaction profiles, and how conditions are controlled to manage rate and yield.

Concentration in grams and moles per cubic decimetre, calculating concentration, the method and apparatus of a titration, and calculating an unknown concentration from titration results.

Methods for following the rate of a reaction, calculating mean rate from quantity and time, drawing and interpreting rate graphs, and finding the rate at a given moment using a tangent.

Collision theory, the factors affecting the rate of reaction (concentration, pressure, surface area, temperature and catalysts), and explaining each factor in terms of the frequency and energy of collisions.

Reversible reactions, dynamic equilibrium in a closed system, the energy changes in the two directions, and Le Chatelier's principle applied to changes in concentration, temperature and pressure.

The sub-atomic particles and their relative masses and charges, the nucleus and electrons, atomic number and mass number, isotopes, relative atomic mass, and the size and scale of atoms.

The historical development of the atomic model from Dalton to the nuclear model, including the plum pudding model, the alpha particle scattering experiment, the discovery of the nucleus, Bohr's shells, and the discovery of the neutron.

The arrangement of electrons in shells (energy levels), writing electronic configurations for the first 20 elements, and the link between the number of outer-shell electrons and an element's group and chemical behaviour.

The particle model, the three states of matter, changes of state, the energy and arrangement of particles in solids, liquids and gases, and the limitations of the simple model.

The structure of the periodic table, the work of Mendeleev, metals and non-metals, and the trends in reactivity and properties of Group 1 (alkali metals), Group 7 (halogens) and Group 0 (noble gases).

Paper chromatography and Rf values applied to identifying substances, the advantages of instrumental methods of analysis, and using flame emission spectroscopy to identify and measure metal ions.

Metal ores and oxidation, extracting metals by reduction with carbon, extracting reactive metals by electrolysis, the position of carbon in the reactivity series, and predicting reactions of Group 1 and Group 7 elements.

Tests for negative ions (anions): the carbonate test with acid, the halide test with silver nitrate, and the sulfate test with barium chloride, including the observations and ionic equations.

Flame tests for metal ions, the use of sodium hydroxide to identify metal ions by precipitate colour, and the tests for hydrogen, oxygen, carbon dioxide, chlorine and ammonia.

The reactivity series of metals, the reactions of metals with water, oxygen and acids, displacement reactions, and using the reactivity series to predict reactions.