Chem

• Topic 1: Properties of Matter
• Inquiry question: How do the properties of substances help us to classify and separate?
• Students explore homogeneous mixtures and heterogeneous mixtures through practical investigations
• Students explore

  1. Homogeneous mixtures and heterogeneous mixtures through practical investigations

  2. Separation techniques based on physical properties

  3. Calculating percentage composition by weight of elements and compounds

  4. Investigating the nomenclature of inorganic substances using International Union of Pure and Applied Chemistry (IUPAC) naming conventions

  5. Classifying the elements based on their properties and position in the periodic table through their physical properties and chemical properties
• Element

  Substance whose atoms all have the same number of protons
• Compound

  Substance made up of two or more different chemical elements combined in a fixed ratio
• Mixture


  Compound made up of two or more chemical components that are not chemically linked
• Homogeneous

  A substance is homogeneous if its composition is identical wherever you sample it
• Heterogeneous


  A mixture in which the composition is not uniform throughout
• Physical Property


  Characteristic of a substance that can be observed or measured without changing the substance
• Chemical Property


  Specific characteristic of a substance like an element or a compound, relating to how it can change as a result of a reaction
• Percent composition

  Tells you by mass what percent of each element is present in a compound
• Inorganic


  A chemical compound that lacks carbon and hydrogen bonds
• Physical Properties of Matter can be measured to describe matter without changing the object: Size, Density, Mass, Freezing Point, Boiling Point, State, Conductivity, Viscosity, Volume, Colour, Flexibility, Permeability, Solubility, Hardness
• Chemical Properties of Matter are properties that are observed during Chemical Reactions: Flammability, Oxidation State, Toxicity, Reactivity to Water, Radioactivity, Chemical Stability
• How does the substance react to the presence of air, acid, base, water, and other chemicals?


  Properties determined without changing the identity of the substance
• Do the properties depend on the amount of substance?

  Physical Properties: Yes, Chemical Properties: No
• Intensive Physical Property

  • Color
  • Melting point
  • Boiling point
  • Density
• Extensive Physical Property

  • Mass
  • Volume
  • Length
  • Shape
• Examples of Mixtures

  • Air
  • Sea water
  • Concrete
• Examples of Compounds

  • Water
  • Salt
  • Copper sulfate
  • Ethanol
• Type of particle present

  • Compound: Contains 2 or more elements, chemically bonded together in a fixed ratio
  • Element: Pure, only one type of atom present
• Compound

  • Cannot be separated into parts by any physical process
  • Can be separated into its elements by chemical decomposition
• Element

  Cannot be separated into parts by any physical or chemical process
• Examples of Compounds

  • Water
  • Salt
  • Copper sulfate
  • Ethanol
• Examples of Elements

  • Oxygen
  • Iron
  • Copper
  • Lead
  • Chlorine
• Separation Techniques

  1. The physical properties of the components of a mixture can be used to separate them

  2. Methods include sieving, filtration, vaporisation, distillation, fractional distillation, sedimentation, decantation, using a separating funnel, adding a solvent then filtering
• Separation methods and the physical properties they depend upon

  • Sieving: Particle size
  • Filtration: One substance a solid, the other a liquid or solution; particle size
  • Vaporisation (evaporation or boiling): Liquid has a much lower boiling point than the solid
  • Distillation: Big difference in boiling points
  • Fractional distillation: Significant but small difference in boiling points
  • Sedimentation and decantation: Density
  • Using a separating funnel: Components are immiscible liquids; different densities
  • Adding a solvent, then filtering: One substance is soluble in the chosen solvent, while the others are insoluble