Home : Structures : Dissolving
We have learned during the last few lessons that everything is made of particles and that these
particles are always moving. In a solid the particles move the least, however, in a gas
the particles move the most.
In the right conditions, when solid particles meet liquid particles they can mix together to form a special mixture called
a solution. This process is called dissolving.
This process doesn't happen when any solid or liquid meet (your glass doesn't dissolve when you put water in it) only when the
right solid meets the right liquid. When they do dissolve, the solid part is called the solute and the liquid it dissolves in
is called the solvent.
There is a link between dissolving and diffusing the main difference is that dissolving
involves the breaking of bonds like those that hold solid particles together.
Once a solvent and a solute dissolve the particles mix together and then diffuse to form an even mixture of particles.
When you put some sugar in your coffee you want the solid sugar to
dissolve in the liquid coffee to give a sweet solution.
If you want your sugar to dissolve quickly you can do two things. We know that temperature can
affect particles - so heating up your coffee will speed up the dissolving process.
The size of the grains of sugar that you use will also affect the speed with which it
dissolves. If you put fine, caster sugar in your coffee it will dissolve quickly; big sugar crystals (found in posh coffee shops)
will dissolve much more slowly.