2024 term 2 science

• Particle model


  All matter is made up of units called particles. The particles are made up of atoms.
• States of matter


  • Solid
  • Liquid
  • Gas
  • Plasma
• Pure substances


  Made up of the same type of particles
• Groups of pure substances

  • Elements
  • Compounds
• Elements


  Pure substances which are composed of only one type of atom (all matter on the periodic table are elements)
• Compounds


  Substances which are formed by 2 or more different types of elements
• Mixtures


  Made up of different particles and substances
• Types of mixtures


  • Homogeneous
  • Heterogeneous
• Homogeneous mixtures


  You cannot see the different compounds because the compounds are evenly distributed
• Homogeneous mixtures

  • Tap water
  • Coffee drink
  • Soda
• Heterogeneous mixtures


  You can see the different compounds because they are not evenly spread
• Heterogeneous mixtures


  • Salad
  • Pizza
  • Cereal
• Atoms


  The smallest part of a substance that cannot be broken down chemically
• Particles are made of atoms
• Independent variable


  Something that does not change by any other variable
• Dependent variable


  Something that changes depending on the independent variable
• Controlled variable


  Something that stays the same throughout the experiment
• Solution


  A type of mixture where one substance (solute) is dissolved into another substance (solvent)
• Solution

  • It is uniform, or homogeneous, throughout the mixture
• Soluble


  Stuff that can dissolve
• Insoluble


  Stuff that cannot dissolve
• Solute


  Dissolves in a liquid to form a solution
• Solvent


  Liquid in which a solute is dissolved
• Suspension


  A mixture, usually cloudy, where one component is suspended in another, but only if the mixture is stirred or shaken. Over time the mixture will separate if not shaken. The solid that settles is called the sediment.
• Emulsion


  A suspension but is a mixture of droplets of one liquid in another liquid. It will settle into two layers if it is not stirred. It can also be cloudy.
• Emulsion


  • Oil
  • Vinegar
• Colloid


  A mixture where the particles are small enough to stay suspended even if the mixture isn't stirred. They never separate. They are always cloudy.
• Colloid


  • Paint
  • Fog
  • Shaving cream
• Decanting

  . Decanting is simply pouring the liquid out of a container, leaving the solid particles behind.
• Sieving

  . Sieving is using a barrier with holes in it to separate large particles from smaller particles. The bigger particles stay behind, and the smaller particles fall through the holes. e.g. colanders, fishing nets and sifters.
• Filtration

  . Filtration, or filtering, also filters large particles from smaller ones, but it often used way smaller holes then a sieve, the holes are often microscopic in size.

  . Filtration is often used to separate an insoluble solid (the residue) from the liquid that gets filtered (filtrate).
• Magnetic separation

  . Magnetic separation uses a magnet to pick up all the magnetic parts in a mixture, leaving the non-magnetic parts behind.

  . Magnetic separation is often used on mine and recycling plants.
• Centrifuging

  . A centrifuging is a machine that spins very, very quickly. By doing this the particles are forced to the sides, and then bottom of the chamber.

  . Centrifuging is used for blood tests.
• Evaporation

  . Separate dissolved solids (solutes) from a liquid or solvent in a solid- liquid solution.

  . The liquid gets heated, then the water evaporates and turns into vapour, leaving the solid behind.
• Distillation

  . Is 1. Separate solvent from a solution

  2. Separate a mixture of liquids (based on their different boiling points)

  . A solution is heated so that it's solvent boils and escapes as vapour. The vapor is then cooled and condensed into a liquid (distillate)
• Chromatography

  . Separates different chemicals, specifically colouring agents (dyes and inks).

  . You draw a dot on the chromatography paper, then you place the paper in a beak with a solvent. The solvent travels up the paper, carrying the ink with it, then the ink separates into all of the different coloured components.

  . It also distinguishes between pure and impure substances.