Are these notes with accidentals chromatic?

Question

I'm having some difficulty deciding which notes with accidentals are considered as chromatic, and was wondering if someone could confirm/deny my assumptions about notes in the attached notation of Mozart's String Quartet in D Major, K155.

Bar 2: Chord is G and A# resolves to B. A# is chromatic (or would it not be because this moves from G minor to G major?).

Bar 20: Chord is E. G#'s in this bar are part of E, so not chromatic.

Bar 24: Chord is A. G# is not part of A chord but is leading tone in A major scale, so not chromatic?

Bar 28: Chord is F# minor: B#(C) is tritone of F so is chromatic. G# is 2nd note of F# minor scale, so not chromatic?

Answer 1

Bar 2: Chord is G and A# resolves to B. A# is chromatic (or would it not be because this moves from G minor to G major?).

• A# is a chromatic approach, you're right. (g-minor would need a Bb)

Bar 20: Chord is E. G#'s in this bar are part of E, so not chromatic. from bar 20 we are in A major and E is the dominant of A (secondary dominant of D)

• The G# in Bar 20 is the 3rd of E and leading tone to A and all the further G# in this section your showing have the same function.

Bar 28: Chord is F minor: B#(C) is tritone of F so is chromatic. G# is 2nd note of F minor scale, so not chromatic?

we are still in A major and its related key f# -minor (and not F!)

B# isn't the tritone of F anyway and here B# is a chromatic appraoch to the 5th of f#m (or the 3rd of A major if you want). The G# is still lead tone to A.

The question could be: Is the lead tone of the secondary 5th a chromatic?

Regarding the tonic key D major someone will say "yes" - but as the entire phrase from bar 20 - 30 is in the dominant key of A I would say: No, in my opinion (as this passage is tonisiced to A major).

The term secondary dominant (also applied dominant, artificial dominant, or borrowed dominant) refers to a triad or seventh chord with dominant function set to resolve to a scale degree other than the tonic, with the dominant of the dominant (written as V/V or V of V) being the most frequently encountered.[8] The chord that the secondary dominant is the dominant of is said to be a temporarily tonicized chord. Tonicizations that last longer than a phrase are generally regarded as modulations to a new key (or new tonic).

https://en.wikipedia.org/wiki/Secondary_chord#Mozart_example

So:

Are these notes with accidentals chromatic?

Not all of them. When the section B (bars 17-32) are considered as modulated to A major - then G# will be the diatonic lead tone of this key.

Answer 2

Decide what key you're in. Notes which are not diatonic in that key are, by definition, chromatic.

If you feel we're in A major/F# minor (often pointless to try to distinguish the two) at bar 28, the B# is chromatic, the G# isn't.

Answer 3

I would say tones that are not diatonic to the "local" key are chromatic.

By "local" I mean the various keys to which the music may modulate. So if the music modulates from D major or A major label anything as chromatic if it isn't diatonic to A major.

When the music is modulating the tonality becomes inherently ambiguous - it's between keys - the diatonic/chromatic distinction isn't so clear then. I suppose I would say discontinue using the key the music last departed and consider things relative to the key the music will next arrive. That isn't a rule. It's just how I think I would first try to understand the tonal direction of the music in terms of diatonic/chromatic.