Chapter 2

• Solute


  A substance that dissolves into another and is added in a small scale
• Solvent


  A substance in which another substance dissolves into and is added in a large scale
• A solution is always transparent, but may be colourless or have a colour
• Colourless solutions


  • Sugar solution
  • Salt solution
  • Hydrochloric acid
• Coloured solutions


  • Copper sulfate (blue)
• When a solid dissolves

  1. It breaks down into smaller particles that spread throughout the solvent

  2. The solvent particles vibrate and slide past one another, bumping into the solute particles which makes them mix

  3. The solvent particles separate all the solute particles, and they are no longer visible
• When a solute dissolves in a solvent, it has not disappeared (the solute particles are still in the solvent)
• Mass of solute + mass of solvent = mass of solution (no mass has been lost, it has been conserved)
• Soluble


  If a solute dissolves in a solvent
• Insoluble


  If a solute does not dissolve in a solvent
• Solubility


  How soluble a substance is
• As temperature increases


  Solubility increases
• Concentrated solution


  A solution that contains more solute particles than solvent particles
• Dilute solution


  A solution that contains more solvent particles than solute particles
• Saturated solution


  A solution where no more solute particles will dissolve
• Independent variable


  The variable you change
• Dependent variable


  The variable you measure
• Control variables


  The variables you keep the same
• The independent variable always goes along the horizontal axis (x-axis), the dependent variable always goes up the vertical axis (y-axis)
• Paper chromatography


  A technique used to separate colours, the resulting image is called the chromatogram
• The baseline on the chromatography paper is drawn using a pencil, not ink, so the ink doesn't mix with the other colours