Scheme of work Physics – Particle model of matter This resource provides guidance for teaching the Particle model of matter topic from our new GCSE Physics (8463). It has been updated from the draft version to reflect the changes made in the accredited specification. There are many changes throughout the document particularly in the opportunities to develop and apply practical and enquiry skills and communication skills. The scheme of work is designed to be a flexible medium term plan for teaching content and development of the skills that will be assessed. It is provided in Word format to help you create your own teaching plan – you can edit and customise it according to your needs. This scheme of work is not exhaustive; it only suggests activities and resources you could find useful in your teaching. 4.3 Particle model of matter 4.3.1 Changes of and the particle model Spec ref. Summary of the specification content Learning outcomes What most candidates should be able to do Suggested timing (hours) Opportunities to develop Scientific Communication skills Opportunities to develop and apply practical and enquiry skills Self/peer assessment opportunities and resources Reference to past questions that indicate success 4.3.1.1 How to determine the density of a material. Equation for density should be known. The density of a material is defined by the equation: 1 Define density. Describe how the density of regular and irregular shapes can be found by experiment. Required practical Use appropriate apparatus to make and record the measurements needed to determine the densities of regular and irregular solid
density, ρ, in kilograms per metre cubed, kg/m3 mass, m, in kilograms, kg volume, V, in metre cubed, m3 Convert non-standard units into standard units for calculations. Recall the equation for density and it. Calculate the density, mass or volume of an object given any two other values. objects and liquids. Volume should be determined from the dimensions of regularly shaped objects and by a displacement technique for irregularly shaped objects. Dimensions to be measured using appropriate apparatus such as a ruler, micrometer or Vernier callipers. (8.2.5) Why do objects float? This topic can be linked to the above investigation as once you know the density of an object you can predict if it floats or sinks in water. 4.3.1.1 The particle model of matter. The particle model can be used to explain the different states of matter. 1 Draw diagrams to show the particle arrangements in solids, liquids and Describe and explain the different particle arrangements in solids, liquids and gases due to the bonds between the atoms. Describe the motion of particles in solids, liquids and Describe and explain the limitations of the particle model of matter, in particular that the particles within the substance Why are models used in Physics? Critically evaluate the models used to describe and explain the behaviour of solids, liquids and If you have a kinetic model, you can use it to demonstrate the motion of particles in a liquid/gas. If you don’t have a model, use a tray, filled with ping-pong balls (or marbles),
are not solid spheres and that the forces between the particles are not represented. and shake it. You can vary the number of ping-pong balls to demonstrate the three states. 4.3.1.1. The particle model of matter to explain density of materials. The differences in density between the different states of matter to be explained in terms of the arrangements of the particles (atoms or molecules). 0.5 Explain why the different states of matter have different densities in terms of mass and volume of the material.. Draw diagrams to show the particle arrangement of solids, liquids and gases. Use the diagrams to explain the differences in densities between solids, liquids and gases. Make models of solids, liquids and gases using plasticine. Does the model produced show the 3D structure of these states? Use the model of the tray filled with ping-pong balls if you haven’t done it in The particle model of matter lesson. Evaluate the models used to explain the properties of solids, liquids and gases. How well do these models cope with water which is less dense than ice (solid water)? Cyberphysics – The Particle Theory – states of matter 4.3.1.2 Changing the state of a substance. When substances change state (melt, freeze, boil, evaporate, condense or sublimate), mass is conserved. 0.5 Why do substances change state? Why does the temperature of a substance remain constant when the substance is changing state? Explain how, when a substance changes state, the mass of the substance is unchanged as there is still the same number of atoms in the substance and it is just Find, by experiment, the melting point of salol. Compare value obtained with true value. Is there a discrepancy? How do you account for the discrepancy?
their arrangement that has altered. Describe the changes of state in terms of solids, liquids and gases. 4.3.1.2 Chemical and physical changes. Changes of state are physical changes; the change does not produce a new substance. If the change is reversed the substance recovers its original properties. 0.5 What is the difference between a chemical and a physical change? Describe the difference between a chemical and a physical change and provide examples for both types. Describe how, if a physical change is reversed, the substance will recover its original properties. Demonstrate physical and chemical changes and, where possible, the reversibility of a physical change, eg melting ice and then refreezing. 4.3.2 Internal energy and energy transfers Spec ref. Summary of the specification content Learning outcomes What most candidates should be able to do Suggested timing (hours) Opportunities to develop Scientific Communication skills Opportunities to develop and apply practical and enquiry skills Self/peer assessment opportunities and resources Reference to past questions that indicate success
reasons for the explosion in terms of gas pressure. Why do aerosol deodorants say: keep away from fire? Why do car tyre pressures have to be checked when cold, rather than after a long drive? Find out why gas cylinders explode in fires (if not, look at questions above). Write a newspaper article on an explosion caused by exploding gas canisters explaining the reasons for the explosion in terms of gas pressure. Explain why a balloon dipped into liquid nitrogen becomes smaller. Heat the water taking the temperature and pressure. Plot a graph of pressure against temperature. 4.3.3.2 How changing the pressure of a gas affects the volume of the gas. (Physics only) A gas can be compressed or expanded by pressure changes. The pressure produces a net force at right angles to the wall of the gas container (or any surface). 1 Explain why it is easy to compress a gas, but not solids or liquids. Describe the effect of taking a balloon underwater: why does the balloon compress as it gets deeper? Why do scuba divers suffer from decompression sickness if they surface too quickly? What does a barometer measure and how does it work? Have two sealed syringes: one filled with water, the other with air. Show you can compress the air one, but not the one filled with water. clip YouTube:
pressure, p, in Pascals, Pa volume, V, in metres cubed, m3 upon the volume of gas inside the container. Explain using the equation how increasing the volume of a container will lead to a decrease in pressure quantitatively. Find out why the CO2 cartridges used by cyclists to inflate their tyres have an insulating material placed around the cartridge. a carbon dioxide cylinder being opened a camping gas cylinder being used. 4.3.3.3 Work done on a gas and the change in internal energy caused. HT only. Work is the transfer of energy by a force. Doing work on a gas increases the internal energy of the gas and can cause an increase in the temperature of the gas. 1 Explain how doing work on an enclosed gas in a given situation, eg a bicycle pump, leads to an increase in temperature of the gas. Find out why gas cylinders may freeze if they are opened and the gas inside is allowed to escape too quickly. Examine the drawbacks of using a pump to compress a gas in terms of an increase in the kinetic energy of the particles and an increased gas pressure on the walls of the container. Put a balloon over a drinks bottle and place the bottle in a beaker of hot water. The balloon should inflate. Carefully remove the bottle and place it in ice water, the balloon should deflate. Place a bung containing a glass delivery tube in a round- bottomed flask, add a small amount of water and heat it. Once steam is coming out of the tube, quickly invert the flask and place the tube into a 100 ml beaker containing coloured water. Video clip YouTube: