The difference between metals and non-metals - Science Gr 4-5

On Earth we find different types of materials like glass, plastic and wood.  

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Metals and non-metals are 2 classes materials can be divided in and have special properties.  Properties is something you can say about a specific material like for instance you can say a solid takes up space and keeps its shape.

If you want to make anything, you will have to first decide what is the purpose of the product (what do you want to do with it)

 If you want to build a desk, you are going to use wood or steel because it is strong.  If you decide on the purpose you will be able to decide what type of material you will use.

Metals and non-metals differ from one another and have different properties.

Metals

      

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Metals are usually shiny.  The light will reflect off the piece of metal and the surface of a metal is called the luster.

Most metals feels heavy and their molecules (the parts it is made of) is packed closely together, so we say it is dense.

Metals are good conductors of electricity and heat - this means the heat and electricity will move through it quickly.  If you put one part of the metal in a fire and touch the part that is not in the fire a bit later it will also be hot.  The reason is because the heat moves through the metal.

         

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We can make metal into sheets, which means it is malleable and can also make thin wire from it so we say it is ductile.

Most metals can be heated to a high temperature and not change its shape.  That is why people make pots from metals.  Another reason is because it if a good conductor of heat, the pot will get warm fast.

Where does metals come from? It is mined from the earth.  Watch the video on the story of metals.

Non-metals

          

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Non-metals have different properties from metals.

Non-metals are not shiny and mostly dull - think of plastic.

Most of the non-metals you can bend, but they are brittle which means it will break if you bend it too much.

Non-metals are insulators - this means they do not conduct electricity and heat as well as metals - the electricity and the heat does not move through it quickly.  This is why the copper wire in the electrical cord (which is a metal and a good conductor of electricity) is covered with plastic (an insulator) that you do not get shocked.

                                             

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Comparing metals and non-metals (Summary)

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• Metals are mostly solid and strong where non-metals are soft and flexible like rubber.
• Metals are malleable and ductile where non-metals can be brittle like glass.
• Metals are shiny and non-metals are dull
• Metals feel cold if you touch it and non-metals are neither cold nor hot

Watch the video on metals and non-metals

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