- Non-metals are elements that accept or gain electrons to generate negative ions.
- They often have 4, 5, 6, or 7 electrons in their outermost shell.
- They are excellent heat and electricity insulators.
- They are usually gasses, although they can also be liquids.
- Carbon, Sulphur, and Phosphorus are solid at normal temperatures.
- Diamond and Iodine are lustrous non metals.
- Fluorine is the nonmetal with the highest reactivity. It does not exist in nature as a free element.
- Liquid non metal at room temperature is bromine.
Properties of Non-Metal:
- The atoms of non-metals tend to be smaller than those of metals. Several of the other properties of non-metals result from their atomic sizes.
- Non-metals have high electronegativities. This means that the atoms of non-metals have a strong tendency to attract more electrons.
- Non-metals have high electronegativities. This means that the atoms of non-metals have a strong tendency to hold on to the electrons. In contrast, metals easily give up one or more electrons to non-metals, metal therefore easily form positively charged ions, and metals readily conduct electricity.
Physical Properties of Non-Metal:
- Some non-metals are found as gases, others as solids, and one is found as a liquid under normal temperature and pressure.
- In their solid-state, non-metals tend to be brittle. Therefore, they lack the malleability and ductility exhibited by metals.
- Ductility is the property of the material to be stretched into wires but non-metals are not ductile except for carbon, as carbon fibers find uses in a wide variety of industries including sports and music equipment.
- Another property characteristic to metals is absent in non-metals called malleability. They can’t be drawn into sheets as they are brittle and break on applying pressure.
- They are not sonorous and do not produce a deep ringing sound when they are hit with another material. They are also bad conductors of heat and electricity except for Graphite.
Chemical Properties of Non-Metal:
-A non-metal does not react with water but it is usually very reactive in air, which is why some of them are stored in water. For example, one of the highly reactive non-metals is phosphorus and it catches fire when exposed to air that is why it is stored in water to prevent its contact with atmospheric oxygen.
-None of the non-metals is known to react with acids.
-The reaction between non-metals and bases is a very complex one.
- The reaction of chlorine with bases like sodium hydroxide gives products like sodium hypochlorite, Sodium Chloride as well as water.
-Oxides of non-metals are formed when it reacts with oxygen.
- The oxides of non-metals are acidic or neutral in nature.
-When Sulphur reacts with oxygen, we get Sulphur dioxide.
-When Sulphur dioxide reacts with water it forms Sulphurous acid.
-Non-Metals react with metal, generally forming Ionic compounds.
Uses of Non-Metal
- For the preparation of ammonia, nitric acid and fertilizers, nitrogen is used.
- For the purification of water, chlorine is used.
- Hydrogen is very useful as rocket fuel.
- Carbon can be used to make pencils when it is in the graphite form.
- Sulphuric acid is prepared using Sulphur.