How is the molecular arrangement of matter related to the speed of sound?

It is an amazing fact that the speed of sound in air is essentially a function of temperature only. Even very large pressure changes produce only very small changes in the speed of sound.

The speed of sound in air is largely independent the sound amplitude, frequency or wavelength.

Though air pressure does not affect the speed of sound, there is a small dependence on humidity, because humidity makes a small change in average air density.

By far the largest dependence of sound speed is on temperature and speed changes with altitude are primarily caused by the change in temperature with altitude.

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