Does sound show wave-particle duality? We know that light and electrons both show wave-particle duality. Or in other words we can say that they can be both seen as a wave and a particle. Can a similar theory be applicable for sound? Can sound also be explained as a particle as well as a wave?
 A: The notion you should look up and learn about is the phonon. It is a quasiparticle that arises in the quantum description of acoustics in condensed matter. The description is simplest and clearest in regular lattices of atoms / quantum particles, so it doesn't work so well for sound in a gas. But phonons can be thought of as quantums of sound in solid lattices.
Basically, a lattice is modelled as a system of coupled quantum harmonic oscillators, whose Schrödinger equation is very like a classical model of point masses linked by ideal massless springs. The system has eigenmodes with natural frequencies $\omega_j$, and the energy level of $j^{th}$ eigenmode can change only by integer multiples of $\hbar\,\omega_j$, whilst its ground state has energy $\frac{1}{2}\,\hbar\,\omega_j$. The quantum of this energy change $\hbar\,\omega_j$ corresponds to the phonons of the acoustic eigenmode in question.
A: To plainly put what WetSavannaAnimal have said. Yes, sound waves can behave like a particle. When sound wave have enough energy to excite the particles that is use for traveling to their excited state, the sound wave becomes a Phonon.
Phonons act like particles that oscillates relative to each other and no longer function like a wave.
A: no, in the macroscopic world of ordinary mass, sound is adequately and completely understood as just the transmission of air (or other media) alternating densities caused by the vibration of the source. There are no particles being transmitted at all, just as a wave on the surface of a body of water does not imply movement of particles themselves propagating the wave. Sound is not composed of elementary particles. 
