Chemistry seperating mixtures

• What are the three states of matter?

  Solids, liquids, and gases
• How are particles arranged in solids?

  Particles are in a regular arrangement
• How do particles behave in liquids?

  They move around randomly
• What is the arrangement of particles in gases?

  Particles are widely spaced and move randomly
• What are the limitations of particle models?

  • They don’t show forces between particles
  • Real particles aren’t all solid spheres
  • Real particles are arranged in three dimensions
• What does (s) represent in a chemical equation?

  Solid state of a substance
• What does (l) represent in a chemical equation?

  Liquid state of a substance
• What does (g) represent in a chemical equation?

  Gas state of a substance
• What does (aq) represent in a chemical equation?

  Dissolved in water (aqueous solution)
• What does the equation C(s) + O2(g) → CO2(g) represent?

  Solid carbon reacts with oxygen gas
• What happens to substances when they are heated?

  • Solids melt to become liquids
  • Liquids boil/evaporate to become gases
  • Solids can sublime to become gases
• What happens to substances when they are cooled?

  • Gases condense to become liquids
  • Liquids freeze/solidify to become solids
  • Gases can form solids by deposition
• How can the state of a substance be determined?

  By knowing its melting and boiling points
• What is a pure substance?

  Contains a single element or compound
• What is a formulation?

  A mixture of specific ingredients for a product
• What do formulations contain?

  • Active ingredients
  • Other ingredients
• Why are other ingredients added to formulations?

  • Improve taste or appearance
  • Bulking agent for size
  • Emulsifiers for mixing
  • Preservatives for longevity
• What are some examples of formulations?

  • Medicines
  • Foods
  • Cosmetics
  • Cleaning products
  • Fuels
• What is a molecule?

  Two or more atoms bonded together
• What is a molecule of an element?

  Same type of atoms bonded together
• What is a molecule of a compound?

  Different types of atoms bonded together
• What is a solution?

  Mixture of a solute dissolved in a solvent
• What is a soluble substance?

  A substance that can dissolve
• What is an insoluble substance?

  A substance that cannot dissolve
• What is a saturated solution?

  A solution with maximum solute dissolved
• How can substances be classified?

  • Elements
  • Compounds
  • Mixtures
• What is an element?

  Made of one type of atom
• What is a compound?

  Made of different types of atoms, chemically bonded
• What is a mixture?

  Different types of substances, not chemically bonded
• What can particles in substances be?

  Atoms or molecules
• How is 'pure' defined in everyday life?

  As something natural or nothing added
• What are the melting and boiling points of pure water?

  • Melts at exactly 0°C
  • Boils at exactly 100°C
• How do impurities affect melting and boiling points?

  • Decrease melting point and increase range
  • Increase boiling point and increase range
• How can a mixture of an insoluble solid and a liquid be separated?

  By filtration
• How does filtration work?

  Solid cannot fit through filter paper gaps
• How can a dissolved solute be separated from a solution?

  By crystallisation (evaporating the solvent)
• Why is it important not to heat the mixture until fully dry during crystallisation?

  • Solvent or solute may spit out
  • Solute might react or decompose
• How can a mixture of two liquids be separated?

  By distillation
• Why does distillation work?

  Boiling points of the two liquids are different
• What is fractional distillation used for?

  For mixtures of liquids with similar boiling points