L1 | CLASSIFYING MATTER

• MATTER

  • Anything that has mass and volume
  • the more pure a sample of matter is, the better we can predict how it will behave, based on chemical principles
• CLASSIFICATION OF MATTER

  1. PURE SUBSTANCE
  2. MIXTURE
• PURE SUBSTANCE

  • has a definite composition that doesn’t change
• PURE SUBSTANCE

  1. ELEMENTS
  2. COMPOUND
• ELEMENTS

  • just one kind of atom
  • cannot be separated into simpler substances
  • gold, helium
• COMPOUND

  • more than one element
  • always have the same chemical formula
  • H₂O
• LAW OF CONSTANT COMPOSITION

  • Law of Definite Proportions 
  • proposed around 1800 
  • by French chemist Joseph Louis Proust
  • states that compounds always have the exact same formula
• MIXTURE

  • physical blend of two or more substances
  • can vary in their compositions
• MIXTURE

  1. HOMOGENOUS
  2. HETEROGENOUS
• HOMOGENEOUS

  • Greek: homos, “same”
  • same composition throughout 
  • one phase
  • uniform mixture
• HETEROGENEOUS

  • Greek: heteros, “other” “different”
  • multiple phases
  • does not have a uniform composition
• TYPES OF MIXTURE

  1. SOLUTION
  2. SUSPENSION
  3. COLLOID
• SOLUTION

  • homogeneous 
  • mixture of two or more substance, one is dissolved in another
  • the particles cannot be seen; light is not visible when it passes through it
  • cannot be separated using a filter
  • tyndall effect cannot be seen
• SOLUTION

  • Liquid alike 
  • Not all Liquid are Solution and not all Solution are Liquid
• SUSPENSION

  • Particles that spreads through a liquid or gas and settle out after some time
  • heterogeneous 
  • mixture of fluid with undissolved particles in it
  • solid particles may be visible and will settle over time
  • light is visible when it passes through it
  • particles can be filtered out
  • particles are larger than solution and colloid
  • tyndall effect can be seen
• SUSPENSION

  • Gas alike 
  • Not all Gas are Suspension and not all suspension are Gas)
• COLLOID

  • mixture consisting of very small insoluble particles dispersed into a fluid
  • Particles do not settle out overtime
  • Molecules are compactly arranged
  • particles are larger than solution but smaller than suspension
  • tyndall effect can be seen
• COLLOID

  • Solid alike 
  • Not all colloids are solid and not all solid are colloid