Question

Which of the following is a property of non – metals?
A.Low densities
B.Low melting points
C.Poor conductors of electricity
D.All of the above

Answer 1

Elements can be segregated on the basis of their electronic configurations. The atoms of the element which have free valence electrons, tend to donate these electrons to achieve more stable electron configurations. The elements which exhibit this basic characteristic are identified as Metals. On the other hand, the atoms of the metals which do not have free valence electrons, and they accept electrons to form more stable electron configurations are known as non -metals.

Complete Step-by-Step Answer:
Let us now discuss the properties mentioned in the options:
1.Densities: The bonds formed between the molecules of non – metals are generally weak due the weak London forces or dispersion forces. This results in a lower magnitude of forces of attraction. Hence, the atoms in the molecules are loosely bound which thereby increases the volume of the molecule. Hence, non – metals have lower densities as compared to metals.
2.Melting points: As discussed above, the atoms of non – metals are not held together strongly. Because of this, the energy required to break the bonds between the atoms to change the state of the element is also very low. Hence, non – metals have low melting points.
3.Conductivity: The lack of free valence electrons results in the lower conduction of electricity in non – metallic compounds.
Hence, all the properties mentioned in the options are properties of non – metals.

Hence, Option D is the correct option

Note: Other properties of non – metals include high ionization energies, higher electronegativities, lack of lustre, low boiling points, brittle solids, etc. and examples are nitrogen, chlorine, fluorine, helium, etc.