Kinetic Particle Theory (Chemistry)

• Properties and Characteristics of a Solid

  • Closely packed in an orderly arrangement
  • Vibrate and rotate about their fixed positions
  • Forces between particles are very strong
  • Kinetic energy of the particles are very low
• Properties and Characteristics of a Liquid

  • Closely packed in a disorderly arrangement
  • Slide past one another freely throughout the liquid
  • Forces between particles are strong
  • Kinetic energy between particles are low
• Properties and Characteristics of a Gas

  • Far apart in an disorderly arrangement
  • Move randomly and freely in any direction
  • Forces between particles are weak
  • Kinetic energy between particles are high
• Explain why solids have a fixed volume and shape

  Their strong attractive force prevents the particles from breaking away from their fixed positions
• Explain why solids have a fixed volume and shape

  • Particles are arranged in a fixed position and a regular pattern
  • The very strong attractive force prevents the particles from breaking away from their fixed positions
• Explain why solids are not compressible

  • The particles are closely packed together so there are little spaces to squeeze in-between
• Explain why liquids have a fixed volume but not a fixed shape

  • The particles in the liquid have a strong attractive force that prevents them from escaping their positions
  • however, the particles can move about and slide past one another freely
• Explain why liquids can flow easily

  The particles are able to move about and slide past one another
• Explain why liquids are not compressible

  The particles in the liquid are closely packed together
• Explain why liquids take up the shape of the container

  The particles can slide past one another freely throughout the liquid
• Explain why do gases not have a fixed volume and shape

  • The gases can move randomly and freely in any direction
  • The weak attractive force do not allow the particles to be in fixed positions
• Explain why are gases compressible

  The particles are far apart from each other, resulting in more spaces between each particle which makes gases compressible
• Explain why gases flow easily

  The particles move freely at high speeds
• Explain why gases take the shape and volume of the container

  The particles are able to move freely in all directions to occupy every corner of the container
• What is exothermic?

  thermal energy is given out into the surroundings
• What is endothermic?

  thermal energy is taken in from the surroundings
• which processes are endothermic?

  melting, evaporation, boiling, sublimation
• which processes are exothermic?

  freezing, condensation, deposition
• What happens when you heat a matter?

  When temperatures increase, thermal energy of the surroundings are absorbed and converted to kinetic energy of the particles

  At higher temperatures, particles have more kinetic energy which allows them to move faster
• What happens when you cool a matter?

  • When temperature decreases, kinetic energy of the particles are converted to thermal energy and given out to the surroundings
  • At lower temperatures, particles have lesser kinetic energy which makes them move slower
• Where do particles get energy from?

  They get thermal energy from the surroundings which is eventually converted to kinetic energy
• definition of a volatile liquid

  easily evaporated at normal temperatures
• definition of diffusion

  Diffusion is the net movement of particles from a region of higher concentration to a region of lower concentration
• effect of temperatures on the rate of diffusion

  At higher temperatures, the particles possess greater kinetic energy. Thus they are able to move faster, resulting in an higher or increased rate of diffusion
• effect of particle mass on diffusion

  At a given temperature, heavier particles require more kinetic energy to move at the same speed as lighter particles. Hence, heavier particles move slower as compared to lighter particles of the same temperature