1.1 Introduction to the particulate nature of matter and chemical change

States of matter

  • Everything is made up of matter. The characteristics of matter are:
    • Made up of particles – atoms, molecules or ions
    • Particles are in constant motion
    • Occupies a volume in space
    • Has a mass

Properties of three states of matter

Properties of States

Temperature

  • The vibration and movement of particles depend on temperature
  • As temperature increases, KEavg increases
  • The SI unit for temperature is the kelvin (K)
  • Absolute zero is 0 on the kelvin scale (-273° on Celsius scale), and is the temperature at which all movement of particles stops
  • Temperature (K) = Temperature (°C) + 273.15

Changes of State

  • Take water for example:Change of State Water graph
  • As temperature increases, kinetic energy in particles increase, causing change of state
    • Melting and boiling are endothermic reactions – energy is transferred from environment
  • As temperature decreases, kinetic energy decreases, causing reversal of state
    • Condensation and freezing are exothermic reactions – energy is transferred to environment
  • There is no change in temperature while melting, boiling, condensing or freezing,
  • energy is used to break/create attractive forces so change of state can occur
  • Changes of state can be described using the following terms:

 

Change of States

Classification of Matter

Classification of matter

 

  • Ion: A charged species
  • Anion: Negatively charged ion
  • Cation: Positively charged ion

How to balance equations

4 types of chemical reactions

  1. Synthesis
  2. Decomposition
  3. Single Displacement
  4. Double Displacement
    1. Complete Combustion
    2. Incomplete Combustion

State symbols

  1. (s) – solid
  2. (l) – liquid
  3. (g) – gas
  4. (aq) – aqueous

The Atom Economy

  • Is a measure of the amount of starting materials that become useful products.
  • High atom economy means that less waste is created and reaction has a high efficiency
  • Atom Economy

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