When exactly would the use of a whole tone scale come into play. I don't see what purpose it serves in a progression, or over what chords it would sound good to use over.
I realize this is a very vague question but I don't know how to word it in any other way.
Quote by jazkel24

Any bands you're trying to copy/sound like?
It's kind of like the diminished scales, not in sound, but in use, sort of. You wouldn't make chords from the scale, but you would use it in some situaion when you want to create an odd sound. Try it over 7th chords and #5 chords.
^You can create chords from it, but with the knowledge that each note is a whole step apart, it's logical to think that you can only build one chord from it - the same chord, but with 6 different roots.

Look at the C whole tone scale, and build a chord with C as the root..

C - D - E - F# - G# - A# (Bb) - C.

If we build a chord in thirds, we get this..

C - E - G# - Bb - D - F#. Compared to the major scale..

C = 1
E = 3
G# = #5
Bb = b7
D = 9
F# = #11

We get a C7#5#11 chord - but because of the symmetry of the scale, you get exactly the same chord, regardless of the root you start to build on. Effectively, C7#5#11 is the same as E7#5#11, G#7#5#11, A#7#5#11, D7#5#11 and F#7#5#11.

Start building the whole tone scale on E, we get..

E - F# - G# - A# - B# (C) - D - E.

Build a chord using thirds, we arrive at this conclusion..

E = 1
G# = 3
B# = #5
D = b7
F# = 9
A# = #11

We get another _#5#11 chord, this time an E7#5#11 chord. This is true for every note in the C whole tone scale - every note gives you a _7#5#11 chord.

Note here that we have the intervals 1 - 3 - b7. A straight dominant chord - if you see a voicing of a straight dominant chord with no fifth, you know it's safe to play the whole tone scale over it - and use the scale to imply the #5 and #11 altered chord tones.

Notice, these are the exact same notes as the C whole tone scale - and this holds true for every note in the C whole tone scale. Since the whole tone scale contains six notes, using this logic - one whole tone scale is actually six whole tone scales because of its symmetry - knowing this, you can find that there are only 2 different whole tone scales. The C, D, E, F#, G# and Bb whole tone scales and the G, A, B, C#, D# and F whole tone scales.

If you know that C7#5#11 also equals the _7#5#11 chord of any other note in that whole tone scale, you know you can play whatever you play over C#7#5#11 over any other _7#5#11 chord built from the C whole tone scale. Because they are effectively the same chord.

If you see a whole tone chord on a lead sheet that says B7#5 (You won't often see a whole tone chord notated, because it's seldom used - also, the notation 7#5, or 7+, +7 and 7b13 are used as a shorthand to represent a chord built from the whole tone scale, thus writing G7#5 also implies the #11) you know that you can play any note a whole step away from the notes in the chord - if you can play anything a whole step away, logically - you can play anything a multiple of whole steps away, so anything you play one whole step away, can be played two whole steps away and so forth.

This is great for sequences - if you play something two whole steps away from the chord, you can play the same thing three whole steps away, four whole steps away, five whole steps away.. etc - and this lends itself to playing sequences over whole tone chords.

But, this is the reason that the whole tone scale is so ambiguous and is hardly ever used outside of small doses - if you look at everything that can be played using the whole tone scale, we get..

One whole step (A major second)
Two whole steps (A major third)
Three whole steps (An augmented fourth)
Four whole steps (An augmented fifth)
Five whole steps (A minor seventh)

As you can see - you can only make a possible six different intervals playing the whole tone scale - which is only half the possible intervals possible. Using the whole tone scale it's impossible to make an interval of a major seventh, major 6th, perfect fourth, perfect fifth, minor second or minor third - and because of this lack of intervals, the whole tone scale can become boring, quickly - and thus it's seldom use and ambiguity.