Powerpoint lecture covering the following in a modern, concise format: Specification Point 1.3 - Understand the reasons for variations in water quality, including pollution, and the storage and supply of clean water. Complete set of Chapter 1 Lectures are available.

Powerpoint lecture covering the following in a modern, concise format: Specification Point 5.2 - Understand characteristics of a rural environment: landscape, climate, settlement, population, land use, employment, accessibility, management (development or conservation). Complete set of Chapter 6 Lectures are available.

Companion PDF worksheet for Edexcel IGCSE Chemistry Lecture 9 - Formulae and Calculations. Contains short answer questions, an activity requiring lateral thinking and exam-style questions. Specification Point 1.25 - Understand how to write word equations and balanced chemical equations (including state symbols). Specification Point 1.26 - Calculate relative formula masses (including relative molecular masses) from relative atomic masses. Specification Point 1.27 - Know that the mole is the unit for the amount of a substance. Specification Point 1.28 - Understand how to carry out calculations involving amount of substance, relative atomic mass and relative formula mass. Complete set of Chapter 2 Worksheets are available.

Powerpoint lecture and associated PDF worksheet covering the following in a modern, concise format: Specification Point 1.25 - Understand how to write word equations and balanced chemical equations (including state symbols). Specification Point 1.26 - Calculate relative formula masses (including relative molecular masses) from relative atomic masses. Specification Point 1.27 - Know that the mole is the unit for the amount of a substance. Specification Point 1.28 - Understand how to carry out calculations involving amount of substance, relative atomic mass and relative formula mass. Complete set of Chapter 2 Lessons are available.

Companion PDF worksheet for Edexcel IGCSE Chemistry Lecture 10 - Formulae and Calculations Part 2. Contains short answer questions, an activity requiring lateral thinking and exam-style questions. Specification Point 1.29 - Calculate reacting masses using experimental data and chemical equations. Specification Point 1.30 - Calculate percentage yield. Specification Point 1.31 - Understand how the formulae of simple compounds can be obtained experimentally, including metal oxides, water and salts containing water of crystallisation. Specification Point 1.32 - Know what is meant by the terms empirical formula and molecular formula. Specification Point 1.33 - Calculate empirical and molecular formulae from experimental data. Complete set of Chapter 2 Worksheets are available.

Companion PDF worksheet for Edexcel IGCSE Chemistry Lecture 14 - Metallic Bonding. Contains short answer questions, an activity requiring lateral thinking and exam-style questions. Specification Point 1.52C - Know how to represent a metallic lattice by a 2-D diagram. Specification Point 1.53C - Understand metallic bonding in terms of electrostatic attractions. Specification Point 1.54C - Explain typical physical properties of metals, including electrical conductivity and malleability. Complete set of Chapter 3 Worksheets are available.

Powerpoint lecture 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 Lectures are available.

Powerpoint lecture and associated PDF worksheet covering the following in a modern, concise format: Specification Point 3.9 - Describe experiments to investigate the effects of changes in surface area of a solid, concentration of a solution, temperature and the use of a catalyst on the rate of a reaction. Specification Point 3.10 - Describe the effects of changes in surface area of a solid, concentration of a solution, pressure of a gas, temperature and the use of a catalyst on the rate of a reaction. Specification Point 3.11 - Explain the effects of changes in surface area of a solid, concentration of a solution, pressure of a gas and temperature on the rate of a reaction in terms of particle collision theory. Specification Point 3.12 - Know that a catalyst is a substance that increases the rate of a reaction, but is chemically unchanged at the end of the reaction. Specification Point 3.13 - Know that a catalyst works by providing an alternative pathway with lower activation energy. Specification Point 3.15 - Practical: investigate the effect of changing the surface area of marble chips and of changing the concentration of hydrochloric acid on the rate of reaction between marble chips and dilute hydrochloric acid. Specification Point 3.16 - Practical: investigate the effect of different solids on the catalytic decomposition of hydrogen peroxide solution. Complete set of Chapter 6 Lessons are available.

Powerpoint lecture and associated PDF worksheet covering the following in a modern, concise format: Specification Point 4.19 - Know the general formula for alkanes. Specification Point 4.20 - Explain why alkanes are classified as saturated hydrocarbons. Specification Point 4.21 - Understand how to draw the structural and displayed formulae for alkanes with up to five carbon atoms in the molecule, and to name the unbranched-chain isomers. Specification Point 4.22 - Describe the reactions of alkanes with halogens in the presence of ultraviolet radiation, limited to mono-substitution. Specification Point 4.23 - Know that alkenes contain a particular functional group (C=C). Specification Point 4.24 - Know the general formula for alkenes. Specification Point 4.25 - Explain why alkenes are classified as unsaturated hydrocarbons. Specification Point 4.26 - Understand how to draw the structural and displayed formulae for alkenes with up to four carbon atoms in the molecule, and name the unbranched-chain isomers. Specification Point 4.27 -Describe the reactions of alkenes with bromine to produce dibromoalkanes. Specification Point 4.28 - Describe how bromine water can be used to distinguish between an alkane and an alkene. Complete set of Chapter 7 Lessons are available.

Powerpoint lecture covering the following in a modern, concise format: Specification Point 3.7.2 - Populations. Specification Point 3.7.3 - Evolution may lead to speciation. Complete set of Chapter 7 Lectures are available.

Powerpoint lecture covering the following in a modern, concise format: Specification Point 2.10 - Understand the role of enzymes as biological catalysts in metabolic reactions. Specification Point 2.11 - Understand how temperature changes can affect enzyme function, including changes to the shape of the active site. Specification Point 2.12 - Practical: Investigate how enzyme activity can be affected by changes in temperature. Specification Point 2.13 - Understand how enzyme function can be affected by changes in pH altering the active site. Complete set of Chapter 1 Lectures are available.

Powerpoint lecture covering the following in a modern, concise format: Specification Point 2.7 - Identify the chemical elements present in carbohydrates, proteins and lipids (fats and oils). Specification Point 2.8 - Describe the structure of carbohydrates, proteins and lipids as large molecules made up from smaller basic units; starch and glycogen from simple sugars, proteins from amino acids and lipids from fatty acids and glycerol. Complete set of Chapter 1 Lectures are available.

Powerpoint lecture covering the following in a modern, concise format: Specification Point 2.59 - Describe the composition of the blood: red blood cells, white blood cells, platelets and plasma. Specification Point 2.60 - Understand the role of plasma in the transport of carbon dioxide, digested food, urea, hormones and heat energy. Specification Point 2.61 - Understand how adaptations of red blood cells make them suitable for the transport of oxygen, including shape, the absence of a nucleus and the presence of haemoglobin. Specification Point 2.62 - Understand how the immune system responds to disease using white blood cells, illustrated by phagocytes ingesting pathogens and lymphocytes releasing antibodies specific to the pathogen. Complete set of Chapter 3 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 2.90 - Describe the structure and functioning of a simple reflex arc illustrated by the withdrawal of a finger from a hot object. Specification Point 2.91 - Describe the structure and function of the eye as a receptor. Specification Point 2.92 - Understand the function of the eye in focusing on near and distant objects, and in responding to changes in light intensity. Complete set of Chapter 4 Lectures are available.

Powerpoint lecture covering the following in a modern, concise format: 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 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.