particle model of matter

• What does the particle model state about matter?

  Everything is made up of lots of tiny particles.
• How does the particle model explain the behavior of matter?

  It describes how particles move and the forces between them in solids, liquids, and gases.
• What are the three states of matter according to the particle model?

  • Solid (e.g. ice)
  • Liquid (e.g. water)
  • Gas (e.g. water vapour)
• How do the particles in solids behave?

  They are held close together in a fixed, regular arrangement and can only vibrate.
• What is the density of solids compared to liquids and gases?

  Solids generally have the highest density.
• How do the particles in liquids behave?

  They are close together but can move past each other, forming irregular arrangements.
• How does the energy of particles in liquids compare to solids and gases?

  Particles in liquids have more energy than in solids but less than in gases.
• What is the behavior of gas particles?

  Gas particles have almost no forces of attraction, move freely, and travel at high speeds.
• What is density a measure of?

  Density measures how much mass is packed into a given volume of space.
• What are the units of density?

  The units of density are kg/m³ or g/cm³.
• How is density calculated?

  Density is calculated using the formula: Density = Mass / Volume.
• How does the density of a material change when it is compressed?

  Its density increases as the particles move closer together without changing mass.
• What are the steps to find the density of a solid object?

  1. Measure its mass using a balance.
  2. Calculate its volume using a formula or by submerging it in water.
  3. Use the formula: Density = Mass / Volume.
• What are the steps to find the density of a liquid?

  1. Zero the balance with a measuring cylinder.
  2. Pour liquid in increments, recording mass and volume.
  3. Calculate density for each measurement and average the results.
• What is internal energy in a system?

  Internal energy is the total energy of a system's particles in their kinetic and potential energy stores.
• How does heating a system affect its internal energy?

  Heating transfers energy to the particles, increasing their kinetic energy and internal energy.
• What happens to a substance when it is heated enough to change state?

  The particles gain enough energy to break the bonds holding them together.
• What are the changes of state that can occur?

  • Melting
  • Freezing
  • Boiling or evaporating
  • Condensing
  • Sublimating
• What is the significance of a change of state in terms of mass?

  A change of state conserves mass; the number of particles remains the same, just arranged differently.
• What is latent heat?

  Latent heat is the energy needed to change the state of a substance without changing its temperature.
• How does pressure affect the volume of a gas?

  A change in pressure can cause a change in volume, especially in flexible containers like balloons.
• What happens when work is done on a gas?

  Doing work on a gas increases its internal energy, which can raise its temperature.
• How can you do work on a gas mechanically?

  You can do work on a gas by applying a force, such as using a bike pump.
• What happens to the temperature of a gas when work is done on it?

  The temperature of the gas increases as energy is transferred to the kinetic energy stores of the particles.