Question

Why are metals sonorous?
a.) They have high melting point
b.) They are hard
c.) They have elasticity
d.) They have plasticity

Answer 1

Hint: Sonorous refers to the ability to produce sound. Solve this question by keeping in mind the properties that lead to propagation of sound.

Complete step by step answer:
The word ‘sonorous’ means – “capable of producing a deep or ringing sound”.
Metals are characterized by a lesser number of electrons in their outermost orbital. As a result of which electron bonding in metals is highly delocalized (one of the contributing factors being very low electronegativity of metals).
Therefore, when we hit a metal surface, the electron cloud moves extremely easily and very little energy is dissipated. This allows the incoming kinetic energy to be easily propagated as a form of disequilibrium, in the form of a wave.
Since metals have a high elasticity, this wave travels with high speed propagation. Sound requires elasticity for high-speed propagation. Generally, in the scales we live in, wavelengths of many modes of oscillation are in centimeters; these sounds can easily have audible frequencies.
Some examples of sonorous metals – iron, silver, etc.
Due to its sonorous nature, many metals are used in musical instruments.
Therefore, the answer is – option (c) – Metals are sonorous because they are elastic in nature.

Additional Information:
Not all metals are sonorous. This property is seen in sheet metals as they have a relatively low density. High-density metals do not propagate the kinetic energy as easily - owing to additional atomic collisions damping the effect.

Note: Other than being sonorous, metals have many other physical properties such as - strength, malleability, ductility, thermal and electrical conductivity, opacity, and luster.