When a substance dissolves in a liquid a solution is made.
Substances that dissolve are called ‘soluble’.
Substances that do not dissolve are called ‘insoluble’.
The liquid in which a substance dissolves to form a solution is called a solvent.
E.g. – The best solvent in the world is water.
The substance that dissolves is called the ‘solute’.
When a solute dissolves in a solvent, that mixture is called a ‘solution’.
Water is made of very tiny particles. Sugar is made of slightly larger particles. Water particles have small spaces between them. They are close together and always moving. So if you add a teaspoon of sugar to a glass of water, the small moving water particles get between the larger sugar particles. Therefore we can see, sugar dissolves in water. Now you have a sugar solution.
If you add more and more sugar to a glass of water, gradually the amount of water particles will decrease and the amount of sugar particles will increase. Eventually there will be no more water particles to get between the sugar particles. Now you have a saturated sugar solution.
A solution that contains all the dissolved substances it can hold is called a saturated solution. Some substances are very soluble. That means a lot of them dissolve in a certain amount of liquid. Some substances are slightly soluble.
The changing of a liquid into a vapour is called evaporating.
Heat the sugar solution on a saucer. Then the water in the sugar solution can evaporate away leaving the sugar on the saucer.
February 5, 2013