Elements (Metals and Non-metals)
Elements are the fundamental building block of all the matter that we see all around us like the river, rock, earth, the sun, the moon, air, everything else that we can observe.
Elements are grouped as metals or non- metals.
Metals and non-metals are classified according to their physical properties and also their chemical properties and the arrangement of the electrons in the atoms.
The properties of both metal and non- metal are shown below in the table.
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Physical Properties |
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Metals |
Nonmetals |
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Good electrical conductors and heat conductors.
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Poor conductors of heat and electricity.
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Malleable - can be beaten into thin sheets.
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Brittle - if a solid.
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Ductile - can be stretched into wire.
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Nonductile.
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Possess metallic lustre.
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Do not possess metallic luster. |
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Opaque as thin sheet.
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Transparent as a thin sheet.
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Solid at room temperature (except Hg). |
Solids, liquids or gases at room temperature.
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Chemical Properties |
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Usually have 1-3 electrons in their outer shell. |
Usually have 4-8 electrons in their outer shell. |
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Lose their valence electrons easily. |
Gain or share valence electrons easily. |
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Form oxides that are basic. |
Form oxides that are acidic. |
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Are good reducing agents. |
Are good oxidizing agents. |
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Have lower electronegativities. |
Have higher electronegativities. |
