Physical Properties of Elements

The meaning of physical properties refers to those properties of elements that are not associated with their chemical composition or change in chemical composition. In other words, we can say that the physical properties of an element are observable without any change in the identity of the substance. The physical property examples include density, solubility, ductility, malleability, hardness, colour, melting point, boiling points, electrical conductivity, etc. The elements of the periodic table vary in these properties depending upon their nature, i.e. metal, non-metal, or metalloids. There are a total of 118 elements in the periodic table, out of which 92 are metals, 20 are non-metals and 6 are metalloids (acting as metals and non-metals both). Similar groups have the same or slight differences in their physical properties. Let’s study the physical properties of metals and non-metals in detail.

Physical Properties of Metals

The common and basic physical properties of metals of the periodic table are as follows:

• Lustre: Metals usually have a shining surface, i.e. due to the reflection of light because of the presence of free electrons. 
• High melting points: The lattice structures of metals are huge, with strong electrostatic force between the ions and valence electrons. Due to the high electrostatic force of attraction, it requires higher energy to break the bond between the metals, therefore, the melting and boiling points of metals are higher.
• Good conductors of electricity: As we know, metals have normally 1 to 3 valence electrons which are free to move. These free electrons are loosely bound and carry the electric charge even on the little current provided. Thus, metals act as a good conductor of electricity, therefore, widely used in making electric wires (For example, copper wires). 
• Good conductors of heat: Just like electricity, metals are also a great conductor of heat. The reason for this conductivity is the presence of movable free electrons in their valence shell. These free electrons on heating collide with one another, producing an enormous amount of kinetic energy. This kinetic energy then transforms into heat energy. Thus, the metals act as good conductors of heat due to which they are widely used in making utensils for cooking.
• High density: The high density of metals is due to the tightly-packed crystalline structure without any air gaps. The densest metal on the Earth is Osmium, i.e. a rare element found in trace amounts with platinum ores. 
• Malleability: The metals exhibit the property of malleability, i.e. they can be easily moulded or beaten into thin sheets. Metal is malleable when it easily transforms into sheets by hammering or rolling. Amongst all the metals, gold and aluminium are the most malleable, i.e. they are the easiest to make sheets of. 
• Ductility: The ductility of any metal is their characteristic property of conversion into wires on hammering or stretching without breaking. These properties of metals are useful in making electrical wires. Metals such as gold, silver, aluminium are the best examples of ductility amongst metals. 

Physical Properties of Nonmetals

• Brittle: Non-metals have weak bonding due to which they are easily breakable. Thus, the non-metals are more brittle than the metals (except diamond and graphite).
• Bad Conductors of Heat and Electricity: Non-metals are no doubt the bad conductors of electricity and heat because of the absence of free electrons in their valence shell. Electrons in non-metals are not free to carry heat or electricity, therefore they are bad conductors and used as insulators for making handles of utensils.
• Non-lustrous: Non-metals lack free electrons, therefore there is no reflection of light. Thus, non-metals are dull in appearance i.e. without lustre.
• Non-ductile: As already mentioned, non-metals are brittle, therefore, it is not possible to make wires by hammering them. When hammered, the non-metals such as sulphur break, thus they cannot form into wires. 
• Non-malleable: Non-metals are non-malleable due to low tensile strength, i.e. the maximum load any material can hold without breaking or being fractured. 
• Low Melting and Boiling Points: Non-metals are held together by the weak intermolecular force of attraction than the metals, therefore they require lesser heat to break and change into liquids or even gases. 

Physical Properties of Metalloids

Metalloids exist between metals and nonmetals and show some of their common physical properties. The Physical Properties of Metalloids are:

• They resemble metals in appearance.
• They are less conductive than metals but more than non-metals, i.e. semi-conductive. 
• The metalloids tend to be more brittle than metals.
• They tend to exist as solids at room temperature like metals.

Conclusion

The physical properties of an element are observable without any change in the identity or the chemical composition of the substance. The physical property examples include density, solubility, ductility, malleability, hardness, colour, melting point, boiling points, electrical conductivity, etc. The common and basic physical properties of metals of the periodic table are lustre, high melting and boiling point, good conductors of electricity and heat, high density, ductility, malleability, etc. On the other hand, the non-metals are dull, non-malleable, and non-ductile, bad-conductors of heat and electricity, low melting and boiling point, etc. The metals are good conductors because of the presence of free electrons or the valence electrons that carry charges. Similarly, non-metal lacks free electrons i.e. the charge carriers, thus they are bad conductors.