Particle Model of Matter

• What does a charged object create around itself?

  An electric field
• Where is the electric field strongest around a charged object?

  Close to the charged object
• What happens to the electric field as the distance from the charged object increases?

  The field becomes weaker
• What does a second charged object experience when placed in an electric field?

  It experiences a force
• How does the force between two charged objects change with distance?

  The force gets stronger as distance decreases
• What should students be able to do regarding electric fields and charged spheres?

  • Draw the electric field pattern for an isolated charged sphere
  • Explain the concept of an electric field
  • Explain non-contact forces between charged objects
  • Explain electrostatic phenomena like sparking
• What is the particle model used for?

  to explain differences between solids, liquids and gases, and to explain how changes from one state to another happen.
• How do engineers use the particle model?

  When designing vessels for high pressures and temperatures
• Why is it difficult to make a good cup of tea high up a mountain?

  Due to changes in pressure and boiling point
• How is density defined mathematically?

  Density = mass / volume
• What are the units for density?

  Kilograms per metre cubed (kg/m³)
• What can the particle model explain regarding states of matter?

  The different states of matter and differences in density
• What should students be able to do with the density equation?

  Recall and apply it to mass-conserved changes
• How can students model the differences between solids, liquids, and gases?

  By drawing simple diagrams
• How does the arrangement of atoms or molecules explain density differences?

  Materials with particles packed closely together are denser than those with particles more spread out.
• What is the aim of The Required Practical of density?

  • record the mass accurately
  • measure and observe the mass and the volume of the different objects
  • use appropriate apparatus and methods to measure volume and mass and use that to investigate density
• What happens to mass when substances change state?

  Mass is conserved
• How do physical changes differ from chemical changes?

  Physical changes recover original properties
• What is internal energy?

  the total amount of kinetic energy.and potential energy of all the particles in the system.
• What does internal energy consist of?

  Total kinetic and potential energy of particles
• What effect does heating have on a system's energy?

  It increases the energy of the particles
• What can heating change in a system?

  Temperature or produce a change of state
• What factors affect the increase in temperature of a system?

  Mass, type of material, and energy input
• What is the equation for change in thermal energy?

  ∆E = m × c × ∆θ
• What does specific heat capacity measure?

  Energy required to raise temperature of 1 kg
• What should students be able to do with the specific heat capacity equation?

  Calculate energy change during temperature changes
• What is latent heat?

  Energy needed for a substance to change state
• What happens to energy during a change of state?

  Energy changes but temperature remains constant
• What is the equation for energy for a change of state?

  E = m × L
• What are the units for specific latent heat?

  Joules per kilogram (J/kg)
• What are the two types of specific latent heat?

  Latent heat of fusion and vaporisation
• What should students be able to do regarding latent heat?

  • Apply the latent heat equation to calculate energy changes
  • Measure the latent heat of fusion of water
  • Interpret heating and cooling graphs
  • Distinguish between specific heat capacity and latent heat
• How are gas molecules characterized in terms of motion?

  Molecules are in constant random motion
• How is the temperature of a gas related to its molecules?


  It relates to the average kinetic energy
• What happens to gas pressure when temperature increases at constant volume?

  Pressure increases
• How does the motion of gas molecules relate to temperature and pressure?

  Motion relates to both temperature and pressure
• What is the qualitative relationship between gas temperature and pressure at constant volume?

  Temperature increases, pressure increases
• What is the Method For the Density Required Practical of a Solid?

  1. Use a ruler to measure the length (l), width (w) and height (h) of .the solid and multiply the measurements to find its volume.
  2. Place the solid on a scale to discover its mass
  3. Use the equation to calculate the density of the metal.
• What is the Method for the density Required Practical of an irregular Object?

  1. Place the irregular object(stone) on the top pan balance and measure its mass.
  2. Fill the eureka can until the water is level with the bottom of the pipe/outlet.
  3. Place a measuring cylinder under the pipe/outlet ready to collect the displaced water. 
  4. Carefully drop the irregular object or stone into the can and wait until no more water runs into the cylinder.
  5. Measure the volume of the displaced water. 
  6. Use the measurements to calculate the density of it.
• What is the method for the density Required Practical of a Liquid?

  1. Place the measuring cylinder on a scale
  2. Pour water into the measuring cylinder and measure its new mass. 
  3. Measure the amount of water poured in m^3
  4. Use the measurements to calculate the density of the water.