Let's run an experiment which includes all 12 tones. We play each tone and test them while a chord sounds. We will use E Major and E minor chords and the single tones on string 1 (test on all strings - this is a good mapping exercise).
We can really use any audio for these types of experiments. You could record yourself playing any single chord and run the experiment. This is really the simplest way to solo...against a single chord.
As a soloist, ultimately we seek to know how each tone will sound against any type of chord. We provide some examples in the last paragraph.
We start the audio [in this case video - so you can see some chord voicings too] and go fret by fret up the first string [try all strings], playing the tones against the sounding chord, making listening judgments for how each tone 'sits' in or rings against the chord.
If it is 'at home', then the tension level is low and it can be confidently sounded [emphasized] against the Major or minor chord without needing to be directed to another tone [some type of melodic resolution].
If it is tense, what's its directionality? Does it want to resolve in a certain direction? If so, we find that resolution. These tense tones are passing or approach tones to emphasis tones.
Some tones are on the fence. They are okay sitting where they are, but they could go up or down to a neighboring tone [typically a chord tone].
How did you do? You may hear things differently, but we will typically agree at the end of the day. Trust your ear. Feel which direction tension seeks resolution. The above charts are general and in different situations, the resolution or tension level can shift.
I also encourage you to record any particular chord and run the experiment. This exercise is good for hearing, soloing/melody writing, and fretboard mapping.
Again...as a soloist, ultimately we seek to know how each tone will sound against any type of chord. Examples: we know how an A tone will sound against any type of chord...it's a 6 to a C Major chord (consonant), it's a flat 7 to a B Major (creates tension but sounds at home depending on the situation - makes a Dominant 7 sound), it's a 4 to an E Major (wants to resolve to G sharp - a sus4 situation).