Companion PDF worksheet for Edexcel IGCSE Chemistry Lecture 15 - Electrolysis. Contains short answer questions, an activity requiring lateral thinking and exam-style questions. Specification Point 1.55C - Understand why covalent compounds do not conduct electricity. Specification Point 1.56C - Understand why ionic compounds conduct electricity only when molten or in aqueous solution. Specification Point 1.57C - Know that anion and cation are terms used to refer to negative and positive ions respectively. Specification Point 1.58C - Describe experiments to investigate electrolysis, using inert electrodes, of molten compounds and aqueous solutions and to predict the products. Specification Point 1.59C - Write ionic half-equations representing the reactions at the electrodes during electrolysis and understand why these reactions are classified as oxidation or reduction. Specification Point 1.60C - Practical: investigate the electrolysis of aqueous solutions. Complete set of Chapter 3 Worksheets are available.

Powerpoint lecture and associated PDF worksheet covering the following in a modern, concise format: Specification Point 2.22C - Know that most metals are extracted from ores found in the Earth’s crust and that unreactive metals are often found as the uncombined element. Specification Point 2.23C - Explain how the method of extraction of a metal is related to its position in the reactivity series, illustrated by carbon extraction for iron and electrolysis for aluminium. Specification Point 2.24C - Be able to comment on a metal extraction process, given appropriate information. Specification Point 2.25C - Explain the uses of aluminium, copper, iron and steel in terms of their properties. Specification Point 2.26C - Know that an alloy is a mixture of a metal and one or more elements, usually other metals or carbon. Specification Point 2.27C - Explain why alloys are harder than pure metals. Complete set of Chapter 4 Lessons are available.

Companion PDF worksheet for Edexcel IGCSE Chemistry Lecture 24 - Making Salts. Contains short answer questions, an activity requiring lateral thinking and exam-style questions. Specification Point 2.40C - Describe an experiment to prepare a pure, dry sample of a soluble salt, starting from an acid and alkali. Specification Point 2.41C - Describe an experiment to prepare a pure, dry sample of an insoluble salt, starting from 2 soluble reactants. Specification Point 2.43C - Practical: prepare a sample of pure, dry lead (II) sulphate. Complete set of Chapter 5 Worksheets are available.

Powerpoint lecture and associated PDF worksheet covering the following in a modern, concise format: Specification Point 2.40C - Describe an experiment to prepare a pure, dry sample of a soluble salt, starting from an acid and alkali. Specification Point 2.41C - Describe an experiment to prepare a pure, dry sample of an insoluble salt, starting from 2 soluble reactants. Specification Point 2.43C - Practical: prepare a sample of pure, dry lead (II) sulphate. Complete set of Chapter 5 Lessons are available.

Powerpoint lecture covering the following in a modern, concise format: Specification Point 1.4 - Understand how the results of experiments involving the dilution of coloured solutions and diffusion of gases can be explained. Specification Point 1.5 - Know what is meant by the terms: solvent, solute, solution and saturated solution. Complete set of Chapter 1 Lectures are available.

Powerpoint lecture covering the following in a modern, concise format: Specification Point 2.51 - Understand why simple, unicellular organisms can rely on diffusion for movement of substances in and out of the cell. Specification Point 2.52 - Understand the need for a transport system in multicellular organisms. Specification Point 2.53 - Describe the role of phloem in transporting sucrose and amino acids between the leaves and other parts of the plant. Complete set of Chapter 3 Lectures are available.

Powerpoint lecture covering the following in a modern, concise format: Specification Point 2.65 - Describe the structure of the heart and how it functions. Specification Point 2.66 - Explain how the heart rate changes during exercise and under the influence of adrenaline. Specification Point 2.67 -Understand how factors may increase the risk of developing coronary heart disease. Complete set of Chapter 3 Lectures are available.

Powerpoint lecture covering the following in a modern, concise format: Specification Point 4.10 - Describe the stages in the carbon cycle, including respiration, photosynthesis, decomposition and combustion. Complete set of Chapter 6 Lectures are available.

Powerpoint lecture covering the following in a modern, concise format: Specification Point 5.1 - Describe how glasshouses and polythene tunnels can be used to increase the yield of certain crops. Specification Point 5.2 - Understand the effects on crop yield of increased carbon dioxide and increased temperature in glasshouses. Specification Point 5.3 - Understand how the use of fertiliser can increase crop yield. Specification Point 5.4 - Understand the reasons for pest control and the advantages and disadvantages of using pesticides and biological control with crop plants. Complete set of Chapter 7 Lectures are available.

Powerpoint lecture covering the following in a modern, concise format: Specification Point 3.19C - Know that a reversible reaction can reach dynamic equilibrium in a sealed container. Specification Point 3.20C - Know that at dynamic equilibrium the forward and reverse reactions occur at the same rate and the concentrations of reactants and products remain constant. Specification Point 3.21C - Understand why a catalyst does not affect the position of equilibrium in a reversible reaction. Specification Point 3.22C - Know the effect of changing either temperature or pressure on the position of equilibrium in a reversible reaction. Complete set of Chapter 6 Lectures are available.

Powerpoint lecture covering the following in a modern, concise format: Specification Point 3.6.1.1 - Survival and response. Complete set of Chapter 6 Lectures are available.

Powerpoint lecture covering the following in a modern, concise format: Specification Point 4.5.3.4 - Hormones in human reproduction. Specification Point 4.5.3.5 - Contraception. Specification Point 4.5.3.6 - The use of hormones to treat infertility. Specification Point 4.5.3.7 - Negative feedback. Complete set of Chapter 5 Lectures are available.

Powerpoint lecture covering the following in a modern, concise format: Specification Point 4.7.4.1 - Trophic levels. Specification point 4.7.4.2 - Pyramids of biomass. Specification Point 4.7.4.3 - Transfer of biomass. Complete set of Chapter 7 Lectures are available.

Companion PDF worksheet for Edexcel IGCSE Biology Lecture 30 - Coordination in Plants. Contains short answer questions, an activity requiring lateral thinking and exam-style questions. Specification Point 2.83 - Understand that plants respond to stimuli. Specification Point 2.84 - Describe the geotropic and phototropic responses of roots and stems. Specification Point 2.85 - Understand the role of auxin in the phototropic response of stems. Complete set of Chapter 4 Worksheets are available.

Companion PDF worksheet for Edexcel IGCSE Biology Lecture 34 - Hormones. Contains short answer questions, an activity requiring lateral thinking and exam-style questions. Specification Point 2.94 - Understand the sources, roles and effects of the following hormones: adrenaline, insulin, testosterone, progesterone and oestrogen. Complete set of Chapter 4 Worksheets are available.

Powerpoint lecture and associated PDF worksheet covering the following in a modern, concise format: Specification Point 2.1 - Describe the level of organisation in organisms: organelles, cells, tissues, organs and organ systems. Specification Point 2.2/2.3 - Describe the structures and functions of the cell’s organelles, including the nucleus, cytoplasm, cell membrane, cell wall, mitochondria, chloroplast, ribosome and vacuole. Specification Point 2.4 - Know the similarities and differences in the structure of plant and animal cells. Complete set of Chapter 1 Lessons are available.

Companion PDF worksheet for Edexcel IGCSE Biology Lecture 25 - The Heart. Contains short answer questions, an activity requiring lateral thinking and exam-style questions. Specification Point 2.65 - Describe the structure of the heart and how it functions. Specification Point 2.66 - Explain how the heart rate changes during exercise and under the influence of adrenaline. Specification Point 2.67 - Understand how factors may increase the risk of developing coronary heart disease. Complete set of Chapter 3 Worksheets are available.