Dissolving a mixture

In a nutshell

Dissolving is when solutes mix with a solvent to give a solution.

Definitions

Key word	Definition
Dissolving	When a solid is being incorporated into a liquid.
Solute	The solid being dissolved.
Solvent	The liquid the solid is dissolving into.
Solution	A mixture of solute and solvent.
Soluble	A substance that dissolves.
Insoluble	A substance that does not dissolve.
Saturated solution	A solution which will not dissolve any more solute at a given temperature.
Solubility	The measure of how much solute will dissolve in a given solvent.
Kinetic energy	The energy an object has because of its movement.

What happens during dissolving?

When you add a solute to a solvent the bonds in solute particles can sometimes break. These solute particles go onto interact and 'mix' with the solvent particles, forming a solution.

The solute does not vanish - it is still there. This can be confirmed by evaporating the solvent and what you will find is the solute left behind.

Example

Add $10\,g$  of sugar (solute) to $100\,g$  of water (solvent). You will form a solution with a mass of $110\,g$ . There is no reduction in mass.

Science; Pure and impure substances; KS3 Year 7; Dissolving a mixture

1.	Solute
2.	Solvent
3.	Dissolving
4.	Dissolved

Solubility

Increasing the temperature leads to more solute dissolving in the solvent. This is because the particles will have a greater kinetic energy, therefore able to dissolve easily.

Keep in mind that certain solutes will not dissolve in certain solvents.

Example

Salt does not dissolve in petrol.