Examples of Metal Non Metals and Metalloids
Wires being drawn from a piece of gold and sheets being formed from an aluminium block. It is possible because they are metals. What about Diamond and Sulphur? Can we draw wires and beat sheets out of them too? No, because these are non metals. Often, a material can be identified as a metal or a non metal by just looking at it. Comparing their physical properties is the first step towards grouping them into metals and non metals. Let us look into them one by one. Metals are generally solids at room temperature except for mercury which is liquid. They are good electrical conductors and heat conductors. That’s why they are used in electric wires and for making utensils. They are malleable and ductile – which means they can be beaten into thin sheets and stretched into wires. Most metals possess metallic lustre and are opaque as thin sheet whereas non metals are generally solid or gas at room temperature and if solid, they are brittle like carbon and sulphur. They are poor conductors of heat and electricity. They are non ductile and do not possess metallic lustre and are usually transparent or translucent as a thin sheet.
Remembering the physical properties goes a long way in differentiating a metal from a non metal. But, there is more to grouping of substances than by just looking at them. Let’s discuss some chemical properties of metals and non-metals which are very helpful to differentiate them from each other. Metals react with oxygen to form metal oxides. Do all metals react in a similar pattern? No they don’t... Every metal reacts in a unique pattern. Sodium and potassium are highly reactive metals and catch fire when exposed to air at room temperature. Therefore, highly reactive metals are stored immersed in oil as oil prevents them from coming in contact with air.
However, like Sodium, not all metals react with oxygen at room temperature. Some need to be heated before they start reacting with oxygen. The temperature at which a metal reacts says a lot about its reactivity. Copper reacts with oxygen in the air very slowly. Prolonged strong heating is required for it to form copper oxide. Around 75% of the elements are metallic in nature in the periodic table.
All the non-metals are placed in the right side of the periodic table. They are electronegative elements which exist in solid, liquid and gaseous state. Compare to metals, non-metals are less reactive. They have 5, 6 or 7 electrons in their valence shell therefore they tend to accept electron to complete their octet. It makes them electronegative such as fluorine, chlorine, oxygen etc. In the periodic table, there is a zig-zag line between metals and non-metals.
These elements show intermediate properties and called as metalloids such as silicon, germanium etc. This zig-zag line shows the conversion of metallic properties to non-metallic properties. The oxides of metalloids are amphoteric in nature and these elements usually act as semi-conductor. We know that metals are good conductor of heat and electricity whereas non-metals are insulator.