Section 1 - Chemistry

• States of matter

  • Solid
  • Liquid
  • Gas
• Solids

  • Strong forces of attraction between particles
  • Fixed position
  • Vibrate around a fixed point
• Liquids

  • Weaker force of attraction between particles
  • Flow
  • Particles move in a random motion
• Gases

  • Very weak force of attraction between particles
  • Flow with no shape or volume
  • Random, constant movement
• Different States of Substances

  • Melting (solid --> liquid)
  • Sublimation (solid --> gas)
  • Evaporation (liquid --> gas)
  • Freezing (liquid --> solid)
  • Condensation (gas --> liquid)
• Diffusion

  Movement of particles through liquid and gas
• Diffusion

  Movement of particles from an area of higher concentration to an area of lower concentration
• Diffusion of bromine gas


  1. Bromine gas diffuses from one gas jar to another

  2. After 5 minutes the bromine gas has diffused from the bottom jar to the top jar
• Air and bromine particles


  • Moving randomly
  • Large gaps between particles
  • Particles can easily mix together
• Diffusion occurs from an area of higher concentration to an area of lower concentration
• BEFORE: AIR
• AFTER: BROMINE GAS
• B


  • D
• C


  • D
• Potassium manganate molecules diffuse through the solution


  From a region of high concentration to a region of low concentration
• Potassium manganate (VI) solution after 4 hours


  Equilibrium is reached, concentration of particles now evenly spread through the solution
• When potassium manganate (VII) crystals are dissolved in water, a purple solution is formed
• A small number of crystals produce a highly intense colour
• The water and potassium manganate (VII) particles are moving randomly and the particles can slide over each other
• The particles can therefore easily mix together
• Diffusion in liquids is slower than in gases because the particles in a liquid are closely packed together and move more slowly
• Solvent

  The liquid in which a solute dissolves
• Solute

  The substance which dissolves in a liquid to form a solution
• Solution

  The mixture formed when a solute is dissolved in a solvent
• Saturated solution

  A solution with the maximum concentration of solute dissolved in the solvent
• Soluble

  Describes a substance that will dissolve
• Insoluble

  Describes a substance that will not dissolve