#ngscience #mixtures #sifting

Here's how to separate a mixture of sand and stones.

We can use our knowledge of the properties of matter to separate the parts of a mixture in different ways. Such properties include size, density, magnetism, evaporation and boiling point. Sifting is a process that can be used to separate a mixture of solids made up of large and small particles. To separate a mixture by sifting, we use a sieve. A sieve is a tool with a meshed bottom. By sifting a mixture of solids through the mesh, the larger solids remain in the sieve and the smaller solids pass through the holes in the mesh thereby separating the solids. Sifting is often used to separate water and food when cooking. A strainer is a type of sieve often used to separate foods like pasta and rice from the water in which it was cooked.

So, what is a mixture?
A bowl of fruit salad contains different kinds of matter. It contains different kinds of berries. The fruit salad is an example of a mixture. A mixture is two or more kinds of matter that are mixed together. The different kinds of matter in a mixture retain their individual chemical properties, but the mixture may have new properties. It may be different in color, taste or have different melting and boiling points. Take a teaspoon of table salt and stir it into a glass of warm water. After a while, you will not be able to see the salt in the water. The salt dissolves in the water forming a solution of salt water. A solution is a mixture in which the matter has blended completely and remain evenly mixed.

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