5.+Mixtures

**This topic is about different kinds of mixtures and how we separate them.**

Nearly all kinds of stuff we meet in our daily lives are **mixtures of substances**. Substances in a mixture can be easily separated from each other because they are not chemically joined together; they are just mixed.

Some mixtures are made up of different substances **all in the same state** (such as steam added to air by a boiling kettle) and others are made up of substances **in different states** or phases (such as the gas bubbles that give soft drinks their fizz!)

Often **we want to separate the components of a mixture** so it is an important task for scientists to find ways for us to separate things that are mixed up! It turns out that we need **different ways of separating** for different kinds of mixtures. It helps if we **understand the different kinds of mixtures** and scientists do have names for them all. Some of these names sound familiar (such as a gel) some just sound strange (such as a sol).

In most mixtures we label substances for the role they have in making the mixture. For example, in a solution where a substance is dissolved in a liquid the stuff that gets dissolved is called the solute and the stuff in which the solute dissolves is called the solvent. Hint: **Remember that the solvent dissolves the solute and together they form a mixture.**

Here's an animation showing how the **particles of solute mix with the particles of solvent in a solution** @http://www.media.pearson.com.au/schools/cw/au_sch_whalley_sf1_1/int/solution/f6/solution.html

In this animation you can explore what the particles are doing in **three different kinds of mixtures in which the solvent is a liquid**. The mixtures you can play with here are **solution, suspension and colloid**. Pay attention to the sizes of the solute particles and how they move. @http://www.media.pearson.com.au/schools/cw/au_sch_whalley_sf1_1/int/3_solutions.html

Here's a link to a great MIXTURES PAGE. @http://www.chem4kids.com/files/matter_mixture.html (It's a bit advanced for year 7s but I thought you might enjoy the challenge. In this site there are three pages about mixtures. You will need to navigate using the menu on the right hand side of each page).

** SECRET BONUS: If you hunt around this page you will find a hidden link to a special page about mixtures! ** ** Look for a place where the mouse pointer changes to a hand!! **