DIFFERENCE BETWEEN INTENSITY AND LOUDNESS OF SOUND?/
The sound intensity(acoustic intensity) is defined as the sound power per unit area. The S.I. unit of intensity is Watts/m2
The loudness of sound is defined as the degree of sensation of sound produced in the ear. It is actually the perception of sound by the listener.
Pitch is same as the frequency of sound. This term is used by musicians.
Hope it is clear!
Best wishes!!