Metals and non-metals are substances that can be differentiated on the basis of various physical and chemical properties. Metals are the elements that are generally hard as strong metallic bond exists between the atoms. As against non-metals are the elements which are usually soft.
Generally, the elements containing 1,2 or 3 electrons in the valence shell of their structure are known as metals. While the elements with 4, 5, 6 or 7 electrons in their outermost shell are known as non-metals.
A large number of elements present in the periodic table are metals while a minority of elements in the periodic table are non-metals. Here we will understand how the various factors differentiate the two.
Content: Metal Vs Non-metal
Comparison Chart
| Basis for Comparison | Metals | Non-Metals |
|---|---|---|
| Number of electrons | Contains 1,2 or 3 electrons in valence shell (except hydrogen) | Contains 4, 5, 6 or 7 electrons in valence shell. |
| Conducting property | Good conductors | Bad conductors |
| Tensile strength | High | Low |
| Melting and Boiling point | High | Comparitively very low |
| Existence in periodic table | Left side | Right side |
| Nature | Electropositive | Electronegative |
| Bond | Metallic bond | Covalent bond |
| State | Generally solid (exception mercury and gallium) | Solid, liquid and gas |
| Density | High | Low |
| Forms | Cation | Anion |
| Malleability and Ductility | These are malleable and ductile | These are non-malleable and non-ductile in nature. |
| Structure | Hard | Soft |
Definition of Metals
Metals are those substances that are hard and holds the property of thermal and electrical conductivity (except tungsten). These materials are lustrous in nature and thus polishing of such elements gives rise to a reflecting surface.
The reason behind this is that metals have free electrons present in their structure. And these free electrons vibrate when then the surface is exposed to light and thus appears as a shiny surface. However, lead stands as an exception for this particular property because lead is a metal with a dull appearance.
Metals are usually found in solid-state but mercury is an exception as it is a metal present in liquid form. Along with this, sodium and potassium are the metals that can be cut down with a knife without any sort of great force as these substances are not too hard.
Metals can be easily transformed into thin sheets and thus are said to be malleable. Furthermore, metals can be converted into thin long wires hence shows ductility. Also when the metal surface is hit with great force then a ringing sound gets produced thereby showing sonorous behaviour.
As metals have generally 1, 2 or 3 electrons in the outermost shell (except hydrogen). Thus can easily donate electrons thereby forming cations. A metal easily reacts with acid and generates hydrogen gas with a popping sound.
Definition of Non-metals
Non-metals are materials that are soft and possess poor electrical and thermal conductivity. This means that non-metals restrict the flow of electric current through them. However, graphite stands here as an exception because it exhibits good electrical conductivity.
Non-metals do not possess the property exhibited by the metals. They appear to be dull, but elements like iodine and diamonds are the exceptional non-metals that have a shiny appearance.
It generally exists in all 3 forms of matter i.e., solid, liquid and gas. Non-metals in solid form are generally soft and thus completely gets converted into powdered mass after the application of force on it. Thus are said to possess brittle nature.
But diamond is again an exception over here because it is one of the hardest substances hence are not brittle. Non-metals holds 4, 5, 6 or 7 electrons in their outermost shell thus usually have a tendency to accept electrons. Thus it forms anions. These elements exhibit a low degree of melting and boiling point. However, non-metals like silicon and carbon have high melting and boiling point.
Non-metals generally do not react with acid but readily react with air and are said to be great oxidizing agents.
Key Differences Between Metals and Non-Metals
- Metals are considered to be electropositive in nature due to their ability to donate electrons. Whereas non-metals are electronegative as they generally accept electrons.
- Metals are generally found in solid-state but non-metals exist in all the 3 states of matter i.e., solid, liquid and gas.
- Metals shows the property of malleability while non-metals are non-malleable.
- Metals are generally those substances that have a shiny surface and thus are lustrous. Whereas non-metals have non-shiny appearance and thus falls under the category of non-lustrous substances.
- The bond formed between metals is said to be metallic bonding. While the bond formed between two non-metals is a covalent bond.
- Metal possesses high tensile strength as there exists strong attraction between molecules. However, due to weak intermolecular forces, the tensile strength of non-metals is low.
- Metals holds the left side position on the periodic table. But non-metals are usually found on the right side in the periodic table.
- Metals exhibit high melting and boiling point except mercury. As against the melting and boiling point of non-metals are generally low except carbon and silicon.
- Metals show the property of ductility as can be easily drawn into wires on applying force. However, non-metals are not ductile but carbon is a non-metal that exhibits ductility.
- Usually, metals are referred as cations while non-metals as anions.
- Metals are said to be good reducing-agents. But non-metals are referred as good oxidizing-agent.
- Metals possess very high density in comparison to non-metals.
Applications
Metals
- Development of machine tools
- In parts automobiles
- Satellites
- In electricity systems
Non-metals
- For medicinal purposes
- In chemical fertilizers
- In the purification systems
- For making crackers
Examples
Metal
- Copper
- Iron
- Silver
- Gold
- Aluminium
- Lead
- Magnesium
- Sodium etc.
Non-metal
- Oxygen
- Nitrogen
- Carbon
- Sulphur
- Chlorine
- Iodine
- Hydrogen
- Phosphorus etc.
Conclusion
So, from this discussion, we can conclude that mainly the properties of elements, distinguishes a metal from a non-metal. Also, there is a class of elements in the periodic table that are neither metals nor non-metals. As these elements combinely hold the properties of metals and non-metals both hence are known as metalloids and are present at the centre in the periodic table.
Good Informaton
Very helpful and easily understandable