The whole-tone scale is a six-note scale built only from whole steps, so it has no half steps and no clear home note. It sounds dreamy, floating and unresolved, the classic tension color for 7#5 chords.
Formula
The reference key is A whole-tone, the key both diagrams use.
| Degrees | 1 | 2 | 3 | #4 | #5 | b7 |
|---|---|---|---|---|---|---|
| Notes | A | B | C# | D# | F | G |
Steps: W W W W W W. Six whole steps take you back to A an octave higher.
Sound and character
With every step the same size, no note leans toward another, so the ear can't tell where home is. That's why it sounds like a dream or a question with no answer. The 3 and b7 still say "dominant", while the #4 and #5 smear it into something strange.
Where it's used
Jazz, fusion, film and TV scores, and the occasional prog or metal break. It fits dominant 7th chords with a raised 5th: A7#5 (also written A+7 or A7b13) and A9#5. Stack every other note and you get augmented triads: A C# F and B D# G. Use it on a dominant chord that's about to resolve, like A7#5 going to Dm, so the tension has somewhere to land.
The symmetry
Look at the two diagrams. The second one is the same shape moved up two frets, and it holds exactly the same six notes. Every whole-tone shape repeats every two frets, which means there are only two whole-tone scales: one on A (A B C# D# F G) and one on Bb (Bb C D E F# G#). Every other "key" is one of these two with a different root.
How to move it
The root is the amber dot. To change key, slide the pattern so the amber dot sits on the new root: up one fret for Bb whole-tone (the other scale), or keep the shape where it is and call it B, C#, D#, F or G whole-tone, because those use the same notes as A.
The exercises play one octave, then the scale against an A7#5 chord so you hear what it's built for.