Question

Non-metals are brittle while the metals are ductile. Why?
(A) Because of lesser extent of bonding in non-metals.
(B) Because of the greater extent of bonding in non-metals.
(C) Because of the small size of non-metallic atoms.
(D) Because of lower conductivity of non-metals.

Answer 1

Hint:As we know that the properties of a material heavily depends on types and extent of bond formation between the atoms making up a material. We also know that metals possess the delocalized electrons in their orbitals which are free to move which is not the case with non-metals.

Complete answer:As we know that the metals are generally made up of metallic bonds which involve the large cations surrounded by a number of electrons which are mobile meaning free moving.
We know that these metallic bonds are formed by the electrostatic attractions between the positively charged cations and negatively charged delocalized electrons from the outermost valence shell of the metal thereby forming a regular layer which is responsible for the movement of electrons from one place to another.
These electrons serve as a glue that holds all the atoms together. The strong electrostatic force of attraction that metal ions feel when they are surrounded by a sea of electrons is actually quite strong and flexible at the same time. So, when we apply a force, they can be transformed into flat sheets and drawn into wires and they are hard to break. This makes the metals ductile in nature like Iron.
Whereas the non-metals are generally not rolled into wires because they are formed of weak attractive forces and thus can be easily broken if any external force is applied. The lesser extent of bond formation in non-metals makes them brittle. The molecules in many non-metals are not actually held together by bonds, but by weak attraction forces.

Therefore, the correct answer is (A).

Note:Remember that the metals are also good conductors of electricity and heat which is due to the presence of free electrons present in them. As the electrons are not bound to atoms, they can easily flow and conduct heat and electricity. As they are acting as glue, they even prevent the metal from getting broken into pieces whereas non-metals are considered as insulators.