Detailed revision guide for Common Entrance science (with examples and links to revision notes)
Note: Items in black bold type are in level 2 papers only.
Chemistry
The variety of materials
Know the main properties of and an everyday use for a variety of substances:
Gold, copper, graphite, mercury, zinc, aluminium, tin, iron, chromium, lead, glass, plastics, Ceramics, wood, rubber, fibres.
Have some idea about why each substance is suited for the use it is put to, eg aluminium is often used for saucepans because it light and does not corrode.
Know that an alloy is a mixture of two metals. eg brass is an alloy of copper and zinc. Solder is an alloy of lead and tin.
The Bunsen Burner
Know the structure of the Bunsen burner. Know that it should be lit with air hole closed. Know the types of flame ie air-hole closed: cool, luminous flame; air-hole open: hot, blue roaring flame. Centre of pale blue cone is unburnt gas and air (not hot). Hottest part of flame tip of pale blue cone. Safety rules: no flammable liquids near flame, no loose cuffs or hair.
Making a solution
Know the meaning of the following terms: solute, solvent, solution, soluble, insoluble, saturated solution.
solute: The solid that has been dissolved when making a solution (eg the SALT in salty water)
solvent: A liquid that has been used to make a solution (eg the WATER in salty water)
solution: The liquid formed when one substance dissolves in another
soluble : is able to dissolve (eg salt is soluble in water)
insoluble: is NOT able to dissolve (eg sand is insoluble in water)
saturated: a solution is saturated when no more of the solid will dissolve in it
Know that water is the most common of solvents.
Know that alcohol and propanone are two examples other good solvents. Know that the solubility of the solute (ie the mass of solute that can dissolve in 1 litre of solvent) depends on the type of solvent and the temperature of the solvent (eg hot water can dissolve more copper sulphate that cold water). Know that some gases can also dissolve in water (fish obtain their oxygen from the dissolved oxygen in the water) and that the amount of gas that can dissolve decreases as the temperature of the water increases.
Separating mixtures
Know that a pure substance is one substance by itself and cannot be separated further (eg pure water would contain water and NOTHING else. Orange juice is NOT a pure substance as it contains water AND orange flavourings).
Know about the following ways to separate mixtures (including examples, diagrams, and practical details):
Filtration: used to separate a solid from a liquid (eg sand from salty water)
Distillation: used to obtain the solvent from a solution (eg obtain pure water from sea water)
Evaporation: used to obtain the solute from a solution (eg obtain salt from salty water)
Chromatography: used to separate out a mixture of coloured substances (eg obtain the green colour from crushed grass)
Be able to draw the apparatus to carry out each process above.
Know the meaning of the terms: filtrate, distillate, miscible, immiscible, residue
Know that air is a mixture of several gases and can be separated into its component parts by the fractional distillation of liquid air.
Know that a mixture of two liquids like alcohol and water can be purified by fractional distillation and that this relies on the two liquids having different boiling points.
An example of this is obtaining alcohol from wine or beer by fractional distillation.
Know meaning of the terms volatile and fraction.
Know that the liquid that has been filtered is called the filtrate and the solid left after filtering is called the residue.
Know that the liquid that has been distilled is called the distillate.
Know how to test water purity by i) measurement of its boiling point and ii) evaporating samples on a watch glass and observing the residue.
Know the difference between sea, tap and distilled water
Acids and alkalis
Know the name of some common acids and alkalis eg citric acid (lemon juice), vinegar, indigestion powder, washing soda.
Know that an acid can neutralise an alkali. Understand that a neutral liquid (eg water or salty water) is neither acidic nor alkaline.
Know the pH scale of 1 to 14. Less than pH 7 = acid. Neutral = pH 7. More than pH7 = alkali.
Be able to use Universal, Full-Range and Litmus indicators and know the colours that each go in various strengths of acidic or alkaline liquids. Know that an acid will react with an alkali (or base). Know how acid and alkalis can be useful in medicine and agriculture.
The air
Know that the air is a mixture of various gases and know the approximate composition of air: 78% nitrogen, 21% oxygen, 1% argon (and other noble gases eg helium, neon), 0.03% carbon dioxide, water vapour. Be able to use anhydrous copper sulphate to show the existence of water vapour in the air.
Know that rain is slightly acidic due to carbon dioxide dissolving in the rain water.
Know that rusting is a form of corrosion and be able to say how to prevent rusting.
Know how to show that both oxygen and water vapour are necessary for rusting to take place.
Know that oxygen is necessary for combustion and also for respiration, both of which are examples of chemical change.
Know that air contains various pollutants, like carbon monoxide from car exhausts and sulphur dioxide from burning fossil fuels. Know of the dangers of these pollutants and how to help reduce them.
Know that air has mass and be able to calculate the density of air.
Be able to make oxygen by heating potassium permanganate and be able to use the glowing splint test to identify oxygen.
Be able to identify the products of combustion eg be able to show that a burning candle forms carbon dioxide (turns lime-water milky)( and water (turns anhydrous cobalt chloride pink).
Physical change
Know the difference between a physical and chemical change. Know that a physical change is often temporary and results in no new substance being formed eg melting wax, boiling water, dissolving salt.
Know various types of physical change: evaporation, sublimation, condensation, freeze, melt, boil, solidify.
Know how to measure the boiling point of water. Know that water boils at 100oC and freezes at 0oC.
Know that the presence of impurities in the water (eg dissolved salt) will usually raise the boiling point and lower the melting point.
Chemical change
Know that a chemical change always results in a new substance being formed and is usually permanent.
Know various kinds chemical change: burning, oxidation, reduction, decomposition, neutralization.
Examples of chemical change: rusting (oxidation),burning coal (oxidation), removing the acid in acid soil by adding lime (neutralization), silver tarnishing, making lime by heating limestone, forming iron by heating iron ore with coke (reduction)
Know that many chemical reactions result in a change in mass eg copper and magnesium will GAIN in mass because they combine with oxygen. Limestone (calcium carbonate) will LOSE mass because it decomposes and evolves carbon dioxide.
Know that a change in colour or a change in temperature are good indications that a chemical reaction is taking place.
Know, in particular, the effect of heat on copper, copper sulphate, copper oxide, cobalt chloride, magnesium, iodine, sulphur and carbon.
Be able to say what happens when water is added to anhydrous copper sulphate (goes blue and gets warm).
Be able to write the word equation for a variety of simple reactions including: oxidation of copper, carbon, magnesium and sulphur, decomposition of copper carbonate and of anhydrous copper sulphate.
If potassium permanganate is heated oxygen is formed.
This is an example of thermal decomposition
eg copper + oxygen –> copper oxide
sulphur + oxygen –> sulphur dioxide
copper carbonate (heat) –> copper oxide + carbon dioxide
copper sulphate (heat) –> anhydrous copper sulphate + water
Elements
Know that the elements are a group of chemicals that cannot be divided into anything simpler ie cannot decompose, and that there about 100 known stable elements. Know that an element is made up of a single kind of ATOM.
Know that two or more different elements can COMBINE together to form a compound eg magnesium (element) + oxygen (element) forms magnesium oxide (compound) Know the name of several compounds; eg magnesium oxide, water, copper sulphate.
Know that the elements can be divided into METALS and NON-METALS.
Know the name of some common metallic and non-metallic elements eg aluminium, copper, carbon, iron, lead, magnesium, oxygen, sulphur and zinc.
Know the main properties that distinguish metals from non-metals:
Metals conduct electricity and heat, are shiny in appearance, malleable and the oxide, if soluble will dissolve to form an alkaline solution.
Non-metals are usually gases, liquids or brittle solids with a low melting point; do not conduct electricity or heat.
The oxides of non-metals usually dissolve to form acids (note: acid rain).
The oxides of metals are often BASES and can be used to neutralise an acid
eg copper oxide dissolves in sulphuric acid to form copper sulpahe solution.
The oxides of reactive metals will dissolve to form an alkaline solution.
eg magnesium oxide dissolves in water, forming magnesium hydroxide, a mild alkali
Activity series
Be able to use the reactivity series of metals.
Know that metals higher in the series will burn more rapidly in air, react faster with water and dilute acids
eg (i) magnesium burns more rapidly than copper, iron corrodes more than copper
Know that metals higher in the series will be able to replace a lower metal from one of it’s compounds.
eg (ii) if carbon is heated with copper oxide the carbon will reduce the copper oxide forming copper and carbon dioxide gas.
Word equation: Carbon + copper oxide –> carbon dioxide + copper
Know that metals like lead and copper are low down in the series and are used for roofing and piping (because of their low reactivity). That precious metals like gold and silver are used for jewellery and electrical contacts because they have very low reactivity.
Know that most metals are not found in their free state (ie form compounds with other elements) and that a chemical reaction is needed to extract them from the ore.
Be able to write word equations for reaction involving the activity series.
The Sun and Water cycle
Know about the domestic water supply; the need for filtration and treatment. Importance of water as a solvent.
The differences between tap, sea and distilled water (as shown by evaporating the water from them in watch glasses).
Know about the importance of the Sun as our main source of energy and its importance in the water cycle and in producing the energy for waves and wind.
Know about he difference between renewable enrgy (energy from wind, sun, waves and plants) and non-renewable energy (energy from fossil fuels: coal, petrol and oil)
Materials from the ground
Know the uses for arious metals and how they are extracted from their ores
Aluminium: know that aluminium comes from Bauxite (an ore containing aluminium oxide). Know that aluminium is high in the reactivity series and therefore has to be extracted from its ore by electrolysis: this process uses a large amount of electricity which makes aluminium expensive. Aluminium is a light metal used a lot for drink cans , aircraft frames or alloys
Copper: Know that copper can be extracted from Malachite (an ore containing copper carbonate. The malachite is heated so it turns into copper oxide which is then reduced by heating it with carbon. The copper formed can be purified by electrolysis. Copper is used for electric wiring and water pipes.
Iron: Know that iron can be extracted from iron ore (iron oxide) by heating the ore with coke (carbon) in a blast furnace. Iron is a strong metal, but quite heavy. It is used items where strength and cheapness is needed eg bridges, girders or bicycle frames.
Measurement
Know how to use a metre rule to measure distance, a balance to measure mass, and a measuring cylinder to measure volume
Know the metric units for mass (kilogram), time (second), distance (meter), area (square metre), volume (cubic metre, millilitre), density (grams per cubic centimetre).
Know that density = mass ÷ volume (level 1 candidates will be given this formula but need to know how to use it)
Be able to measure mass and volume, and to be able to calculate the density of solids with a regular shape (eg cube), of an irregular shape (eg a small stone) and of liquids.
Have an idea of your own height (in metres) and mass (in kilograms). Be able to estimate the size of some common objects (eg the mass of an apple or the length of an exercise book).
Know how to make and measure the period of a pendulum.
Be able to measure the density of air.
Forces
Know how to measure a force using a spring balance and to know the unit for force (newton). Be able to give examples of different forces: eg friction, gravity, electrostatic and magnetic forces.
Understand about magnets and magnetic fields. Be able to plot lines of magnetic force using either a plotting compass or iron filings.
Know that the weight of an object is caused by the pull of gravity on it and that the unit of weighis the newton. Know the difference between mass and weight: that the mass of an object never changes and that the weight can.
Know that a force is needed to stretch a spring and that the extension of a spring is proportional to the load applied. Know that the elastic limit of a spring is the furthest it can be stretched and still return to its original length. Know the effect of joining two similar springs in series and in parallel .
Know how to plot a graph showing how the extension of a spring varies with the load on it.
Know how a force can effect an object: that a force can change the shape of things and cause things to start and stop moving. Know that friction will cause a moving object to slow down.
Be able to show the forces acting on an object (eg on a flying aeroplane) by marking arrows on the diagram.
Understand the forces that enable floating and sinking.
Know that friction is a force that tries to slow down a moving object. Understand how friction can be a useful force (eg the brakes on a bicycle or car)and how it can be a nuisance (the air resistance of a car slows it down and make it use more petrol).
Be able to measure the speed of a moving object. Know that speed = distance ÷ time. Know how stopping distance is affected by speed. Know how different surfaces will affect stopping distance. Be aware of different braking distances as listed in the Highway Code.
Understand the action of a lever or pulley to change the strength or direction of a force. Understand the relationship between force, area and pressure, ie if the area that a force acts on increases the pressure will go down or that if the area decreases the pressure will go up ; eg i) snow shoes do not sink into the snow because the larger area spreads out a persons weight.
ii) A cheese wire is thin to concentrate the force in one place, increasing the pressure on the cheese.
Pressure
Know that pressure is calculated as pressure = force ÷ area. Know that pressure is measured in newtons per square centimetre (the unit of pressure).
Understand that objects with a large area will exert a small pressure because the weight is spread out (eg standing on skis which stop you sinking into the snow because they have a large area or an elephant standing on some sand does not sink because the feet have a large area that spreads out his weight)
Understand that a small area increases the pressure (eg a drawing pin pushes into the board and not your hand because the point has a small area which concentrates the force on the board)
Know how to solve simple problems like working out the weight of a brick from its mass and then calculating the pressure the brick will exert on a table.
Know that pressure increases with depth (which is why dam walls are thicker at the base, and also explains why our ears ‘pop’ when we go down or up a steep hill)
Moments and Levers
Understand about the law of moments
Clockwise moments = anticlockwise moments
Unit of moments = Newton centimetre N⋅cm (or Newton metre)
Light and Sound
Know that sound is produced when an object vibrates and that sound travels as waves.
Know that sound travels through solids, liquids and air but not through a vacuum.
Know their own audible range and know the relationship between loudness, amplitude, pitch and frequency.
Know that light comes from a luminous source and travels in straight lines.
Know that objects are seen be light being reflected or scattered from them.
Know that light travels much faster than sound. Understand about the reflection, refraction, absorption and transmission of light.
Understand how prisms and mirrors can change the path of light. Be able to make a simple periscope and understand how it works.
Energy
Understand the law of conservation of energy and to know that energy will flow from a body at a high temperature to one of a lower temperature.
Know that energy can exist in several different forms: kinetic (motion) energy; gravitational potential energy; strain (spring) energy; chemical energy; electrical energy; internal energy; sound energy; nuclear energy; light energy.
Be aware that chemical reactions often give out energy (eg magnesium + air; iron + sulphur; calcium + water; a metal + an acid).
Be aware of energy loses that appear in buildings and of ways of reducing them (eg double glazing, loft insulation). Know of different ways that energy can be transferred from one form to another eg i) a light bulb changes electrical energy to light and internal energy; ii) A motor converts electrical energy to kinetic energy.
Know that the joule is the unit of energy. Understand that there is energy contained in hydrocarbons which are used as fuels (eg petrol and oil), and also in coal and wood. The role of the Sun as the ultimate source of energy in all fossil fuels, of the energy stored in plants (captured by photosynthesis) and of changes in weather which make wind and water power possible.
Particle Theory
Know that all matter is made up of tiny particles that are constantly moving. That in a solid the particles are bound tightly together by strong electrical forces and can only just vibrate. That in a liquid the particles are only held by weak forces and can slide over one another. That in a gas the particles are far apart and are moving freely in any direction. Know that the speed of the moving particles will increase if a substance is made hotter.
Know that a gas exerts a pressure because the air particles are knocking against the sides of its container. Know that diffusion is the gradual mixing of two substances and takes place because the liquid (or gas) particles are constantly moving.
Circuits (Electricity)
Know that in order for a current to flow there needs to be a complete circuit. That in order for a current to flow there needs to be a potential difference (voltage) which is produced by a cell or cells. It is this voltage that pushes the electricity around the circuit. That the current will increase if the voltage (number of cells) increases. Know that anything that the electricity has to flow through (eg a bulb) will have resistance and that if the electricity has to flow through the bulb the current will get less. Know that the current will decrease if the resistance of the circuit increases.
Know the meaning of components being in series or parallel. To be able to use an ammeter to measure the current flowing through different parts of a circuit. Know what is meant by a “short circuit” and to say what effect this will have on the current.
Know the symbol for and use of the following components: Bulb, cell, battery, ammeter, diode, variable resistor, fixed resistor, fuse, SPST switch, SPDT switch, push switch, reed switch, light emitting diode (LED), light dependant resistor (LDR) and reed relay.
Be able to draw working circuits containing any of the above components.
Know how to positions, name and colours of the wires in a 13 amp plug. Know the use for the fuse in the plug and how the fuse works (melts when too much current flows through it, so cutting off the electricity supply).Be able to make logic circuits using switchesNOT, AND, OR and NAND gates; be able to draw truth tables for these.
The Earth in Space
Know that the Earth is one of nine planets which orbit the Sun. Understand that the Moon is a satellite of the Earth, and that other planets, like Jupiter, also have moons. Understand what causes night and day, the seasons, and eclipses of the Moon and Sun.
Know that our solar system is part of the Milky Way galaxy, and that the Universe contains many such groups of stars (or galaxies).
Understand a little about the development of manned space flight , and the use for satellites for communication and monitoring conditions on Earth.
Understand that a gravitational force exists between any two bodies, and that this force causes bodies to fall towards the centre of the Earth. It is gravity which gives any object its weight which can be measured in newtons using a spring balance.
Know that the gravitational force between the Moon and the Earth , and between the Sun and the planets which keep the planets and Moon in orbit.
Biology
Cells
Know the name and use of the structures present in all cells (animal and plant):
The nucleus (controls how the cell works); the cell membrane (living outer covering) mitochondria (that supply the cell with energy) and the cytoplasm (living contents of cell).
Know that the nucleus contains the genetic material that decides how future generations will behave.
Know that plant cells also contain a cell wall (made of cellulose. Helps the cell keep its shape), large vacuole (contains cell sap, helps keep the cell rigid) and sometimes chloroplasts (contain chlorophyll. Where photosynthesis is carried out).
Know that cells can be recognised by their shape. Be able to recognise some common cells (muscle cell, nerve cell, red blood cell, sperm cell, plant cell).
Know that cells in a multicellular organism (like a human) cells are grouped together to form tissues, which are part of organs. All the organs form the organism. Know the name and position of the major organs in a human: heart, lungs, brain, intestine, kidneys, liver, testes, ears, eyes, skin, penis, uterus, bladder.
Know that the amoeba is an example of a single celled animal. Know that it reproduces like most single cells, by binary fission, a form of asexual reproduction.
Know how to prepare a microscope slide of some cheek cells. Know how to set up and use a microscope for viewing a slide. Know that magnification = objective lens power x eyepiece power.
Classification
Know the features of the main animal and plant groups and be able to give examples from each:
single-celled organisms, fungi, plants that do not form seeds, plants that form seeds, arthropods (insects and spiders) fish, amphibians, reptiles, birds, mammals and flowering plants.
Know the difference between warm and cold blooded animals, and between vertebrates and invertebrates.
Be able to use a simple key to find out the name or group to which a specimen belongs.
Be able to collect data on features (such as height or mass) of a population and be able to draw a histogram (bar chart) of that data.
Know that the variation between individuals may be explained either by genetic differences or by differences in the environment.
Life processes
Feeding (including digestion) respiration, removal of waste, movement, behaviour, growth, reproduction, response to a stimulus (sensitivity).
Know the function of the kidneys in removing soluble waste.
Know that digestion takes place mostly in the intestine and that enzymes are needed to help digestion take place. That insoluble waste is expelled from the body.Know that the main components of a diet are carbohydrates, protein, fats, vitamins, minerals, fibre and water. Be able to give examples of foods rich in each of the nutrients named above.
Know that a balanced diet is one containing all of the nutrients above in their correct proportions. Understand the importance of exercise and a healthy life-style.
Know the structure and use of blood. That blood consists of red and white blood cells, platelet and blood plasma. Know that blood is needed for the transportation of substances around the body (red blood cells carry oxygen); protects us from diseases (white blood cells kill bacteria); helps regulate body temperature.
Know that respiration is the process by which all cells release energy from sugar.
Know the word equation for respiration: Sugar + oxygen –> carbon dioxide + water + energy
Know that the waste products of respiration are carbon dioxide and water.
Know that our body needs the energy released during respiration for warmth, movement, repair and reproduction of cells, and for chemical processes within the body.
Plants
Know the main features of the plant: root- absorbs moisture dissolved mineral salts; stem- transports water and dissolved food around plant; leaves- where photosynthesis is carried out; flower- contains reproductive organs.
Structure of the flower, pollination, fruit formation, seed structure and dispersal, conditions needed for germination of seeds (oxygen, water and warmth) and for the normal growth of seedlings. Methods of asexual reproduction: runners, budding and cuttings.
Know that photosynthesis is shown by the equation:
carbon dioxide + water + light energy –> sugar + oxygen
Appreciate that light and chlorophyll are needed for photosynthesis. Know that plants require food from the soil in the form of soluble nitrates. If the food is missing poor growth results.
Microbes
Viruses, bacteria and fungi. Diseases caused by bacteria (eg cholera), virus (eg influenza), and fungus (eg athletes foot, potato blight) uses in medicine, agriculture and industry. Know that yeast reproduces by asexual reproduction, and that it respires anaerobically producing alcohol and carbon dioxide, and that this process, called fermentation, is made use of in the brewing and baking industries. Use of bacteria in dairy industry. Know that bacteria are used in the dairy industry in the production of yogurt and cheese.
Human Biology
Know the changes that occur at puberty and the menopause. Understand that sexual reproduction requires two parents, and produces variable offspring. Know the relative size and number of the egg and sperm, and their roles. Understand that fertilization is the fusion (joining) of the egg and sperm, and this brings together some, but not all, of the characteristics of both parents. Understand the terms gamete and zygote. Know that the male gamete in humans is the sperm and the female gamete the egg. Appreciate that the characteristics of the offspring are decided by the genetic material (genes) found in the nucleus of the cells, and this can be the cause of inherited disease. Know about the mating process, the pattern of growth and care of the young. Know the role of the mammary glands. Know that fertilization takes place in the fallopian tube and that the embryo develops in the uterus. Know about the structure and functions of the human reproductive system. Know how the embryo is protected. Know the role of the placenta in supplying food and oxygen and in the removal of waste from the embryo.
Ecology
Have made a study of a habitat and have a knowledge of at least one animal and one plant (eg frog and pond weed or butterfly and pleurococcus), with particular attention to their distribution.
Know what is meant by the terms community, population, habitat, environment and ecosystem. Have an understanding that the environment, producers and consumers are all in a very delicate balance that can easily be upset.
Know the importance of producers in being able to manufacture food by photosynthesis and so provide energy for the rest of the food chain. Have measured physical factors in the habitat, eg temperature, moisture level, acidity/alkalinity (ie pH), and know how these factors might effect the organisms living there. Be aware of changes that may take place between day and night and between the seasons.
Know some simple methods for estimating the population of an organism, eg using a quadrat to measure the population of daisies on a lawn. Understand how population size is effected by competition and by predators.
Be aware of how supplying the needs of a large human population can effect the environment: cutting down trees for paper, ploughing fields for crops. Understand how this can lead to pollution. eg large numbers of cars increases carbon monoxide (a toxic gas) and puts lead in the atmosphere (harms the brain, esp. in children), burning fossil fuels forms sulphur dioxide which causes acid rain. Know that sulphur dioxide and carbon monoxide are called pollutants.
Have considered the balance between the beneficial and harmful effects of industry, agriculture or urban development (making new towns etc) on the local environment. Be able to classify litter should as biodegradable or non-biodegradable; have considered how one small local area could be improved.
Understand that a food chain is a way of representing how energy flows from one organism to another, and that a food web is a combination of food chains. Know that all the energy for the organisms starts from the sun and then absorbed by green plants (producers). The plants are eaten by herbivores which in turn are eaten by carnivores (consumers). Understand that the number of organisms at each stage of the food chain decreases (pyramid of numbers).
Understand the importance of the decomposers (beetles, fungi etc) in the habitat and the role of fungi and bacteria (saprophytes) in recycling nutrients to the plants.
Understand the idea of the carbon cycle as a way of showing the balance between respiration, and photosynthesis, and the effect of this on the atmosphere (ie the balance of carbon dioxide and oxygen).
