Questions: Secondary Dominants: Temporary Tonicization

Question 1

In the key of G major, what chord is V/V (the dominant of the dominant)?

• A. A minor (A–C♮–E)
• B. A major (A–C♯–E)
• C. E major (E–G♯–B)
• D. B major (B–D♯–F♯)

Answer: (B)

G major's dominant (V) is D. To find V/V, ask: what is the dominant chord of D major? D major's dominant is A major (A–C♯–E). In G major, C is naturally C♮, so the C♯ is the tell-tale accidental that marks this as a secondary dominant. A minor would be the diatonic ii chord of G major — it has no dominant function toward D.

Question 2

While analyzing a piece in C major, you notice a chord containing F♯. A classmate concludes the piece has modulated to G major. What is a more likely explanation?

• A. Your classmate is correct — F♯ signals a key change to G major
• B. The F♯ is probably part of a secondary dominant (D major = V/V), tonicizing the G chord momentarily
• C. F♯ is a chromatic passing tone with no harmonic function
• D. The composer made an error in the score

Answer: (B)

An accidental within a passage is the primary diagnostic clue for a secondary dominant — not a modulation. If the music briefly uses D major (with F♯) and then resolves to G (V in C major) before continuing in C, it is tonicizing G without changing key. A true modulation would involve an extended stay in the new key, not just one chord. The two-level thinking skill is learning to distinguish 'visiting' (secondary dominant) from 'moving' (modulation).

Question 3

V/V in C major is D minor, built on the second scale degree with the notes D–F♮–A.

• T. True
• F. False

Answer: False

V/V in C major is D major (D–F♯–A), not D minor. D minor is the naturally occurring ii chord of C major. To function as a secondary dominant, D must have dominant quality — a major triad (or major-minor seventh). The F♯ is borrowed from G major, where D is the dominant. D minor has no leading tone to G and therefore lacks the tension needed to tonicize it.

Question 4

A secondary dominant must resolve to a chord a perfect fifth below it.

• T. True
• F. False

Answer: True

This resolution rule is strict and parallels the ordinary V→I resolution: the secondary dominant (e.g., V/V) resolves down a perfect fifth to its target (V). V/IV resolves to IV; V/ii resolves to ii. The leading tone of the borrowed key resolves upward by a half step, and the fifth resolves downward, creating a local sense of arrival. A secondary dominant that doesn't resolve this way loses its functional identity.

Question 5

What does it mean to 'hold two levels of tonal reference simultaneously' when analyzing secondary dominants, and why is this skill essential for understanding chromatic harmony?

Model answer: It means tracking both the home key (what key is the piece in overall?) and the local key (what is this specific chord pointing toward right now?). A secondary dominant has dominant function relative to its target chord, even if that target is not the home tonic. For example, V/V in C major has dominant function relative to G, not relative to C. You must hold 'we are in C major' and 'this chord is behaving as if G is tonic' in mind at the same time.

This two-level thinking is the conceptual foundation of all chromatic harmony. Diatonic chords have functions only relative to the home key. Secondary dominants introduce a second level: a chord can simultaneously be a non-tonic scale degree in the home key and a dominant in a local context. Failing to think at both levels causes analysts to either miss the secondary function (treating it as just a color chord) or over-interpret it as a modulation.