By David Fowkes on Monday, 13 February 2017
Category: IGCSE Chemistry

1.1 - 1.2 The three states

 1.1 Introducing the states

Matter can exist in one of three fundamental states: Solid, Liquid or Gas

Here we consider the way in which these three states behave

We see how matter can be converted from one state into another and we introduce the terms used for these changes.

Evaporation, condensation, melting, freezing , sublimation and deposition.

It is important to be able to recall and explain the properties and behaviour of solids liquids and gases.

We also look at the way in which some substances dissolve in others and consider the terms :

Solute, solution, dissolve, soluble, saturated solution 

 1.1 - 1.2 Three fundamental states of matter

 Students should:

1.1 understand the three states of matter in terms of the arrangement, movement and energy of the particles

1.2 understand the interconversions between the three states of matter in terms of:

  • the names of the interconversions
  • the names of the interconversions
  • how they are achieved
  • the changes in arrangement, movement and energy of the particles.

 1.2 Activity 1: Properties of the states

 1.2 Activity 2: Name the changes

Heating a material will give energy to its particles and cause them to move more rapidly. Cooling does the opposite. Heating or cooling can therefore cause a material to undergo a change of state.

With three principal states of matter there are six possible changes depending on whether we are heating or cooling the substances. These are shown in the table below.

​Heating ​Cooling
​solid/liquid ​melting ​freezing
​liquid/gas​evaporating​condensing
solid/gas​sublimation​deposition