IB Chemistry - Fundamental

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The nature of the world around us has been the subject of interest and speculation for thousands of years. The original chemistry concerned itself with observing and compiling data on the many substances that could be found free in nature or prepared by simple procedures such as heating. People working with such substances were known as alchemists (from the Arabic 'al quimia') and although much time and effort was put into the search for the philosopher's stone, there was also a great deal of useful information gathered.

The theories underlying the structure of matter waited until the eighteenth century when John Dalton made observations regarding the indivisible particles of matter, which he called atoms.

This section deals with the fundamental ideas needed to understand the nature of chemistry.

Syllabus reference

Structure 1.1.2 - The kinetic molecular theory is a model to explain physical properties of matter (solids, liquids and gases) and changes of state.

  • Distinguish the different states of matter.
  • Use state symbols (s, l, g, and aq) in chemical equations.


  • Names of the changes of state should be covered: melting, freezing, vaporization (evaporation and boiling), condensation, sublimation and deposition.

Tools and links

  • Structure 2.4 - Why are some substances solid, while others are fluid under standard conditions?
  • Structure 2 (all)
  • Reactivity 1.2 - Why are some changes of state endothermic and some exothermic?

In Chapter 0.10