Unit 7 covers two types of applied chords: secondary dominants (major triads or dominant seventh chords built on the fifth of a target chord) and secondary leading-tone chords (diminished triads and diminished seventh chords built on the leading tone of a target chord). Both types use accidentals to create chromatic alterations, and both must follow the same doubling and resolution rules as their diatonic counterparts.
Fiveable's AP Music Theory Unit 7 review covers 4 topics, with guided practice questions for the unit.
Defines tonicization as a local harmonic event and introduces secondary dominant chords (V/V, V/ii, V7/IV, etc.) as the primary means of achieving it. Covers Roman numeral slash notation, chromatic accidental spelling, and the distinction between tonicization and modulation.
Applies 18th-century voice-leading rules to secondary dominants: resolving the chordal seventh down by step, resolving the chromatic leading tone up by step, avoiding doubling the leading tone, and recognizing raised scale-degree patterns in soprano-bass counterpoint.
Introduces diminished triads (vii°6) and diminished seventh chords (vii°7 and viiø7) as applied leading-tone chords. Covers spelling, inversion rules, slash notation, and the difference between fully and half-diminished applied chords.
Extends leading-tone chord voice-leading rules to applied contexts: temporary leading-tone resolution, chordal seventh resolution, doubling restrictions, and avoiding parallel fifths and octaves. Includes score analysis and error detection tasks.
Try AP-style questions on unit 7, then use the review notes below for anything you miss.
Tonicization temporarily makes a non-tonic chord sound like a local tonic by preceding it with its own dominant. The effect is brief and lacks a cadence in the new key, so the primary key never changes. Secondary dominants are spelled by finding the fifth of the target chord and building a major triad or dominant seventh chord on that pitch, adding whatever accidental is needed.
Spell V/V, V/ii, V/IV, and V/vi in G major. Identify which scale degree receives a chromatic alteration in each case and explain why the primary key has not changed.
| Feature | Tonicization | Modulation |
|---|---|---|
| Duration | Brief, one or a few chords | Extended, new key established |
| Cadence in new key | No | Yes |
| Primary key changes | No | Yes |
| Accidentals present | Yes | Yes |
| Roman numeral label | Applied chord (V/x) | New key Roman numerals |
When you part-write a secondary dominant, treat it exactly like a regular dominant chord aimed at a temporary tonic. The chromatic leading tone resolves up by step to the root of the target chord, and any chordal seventh resolves down by step. Avoid doubling the chromatic leading tone. In soprano-bass counterpoint, a raised scale degree moving up by step (such as raised 4 moving to 5) is a common signal that a secondary dominant is implied.
Given a soprano line in D major that moves F#-G#-A, identify the implied secondary dominant, write an appropriate bass line, and check that the chordal seventh and leading tone resolve correctly.
Secondary leading-tone chords tonicize a target chord by acting as its own leading-tone chord. They are built on the pitch a half step below the root of the target chord and come in three forms: diminished triad (first inversion only), fully diminished seventh, and half-diminished seventh. The half-diminished form (viiø7) appears only in major-mode contexts because it naturally occurs on the leading tone of a major key.
In F major, spell vii°7/V and vii°7/ii. Identify which pitch in each chord is the chromatic alteration and name the target chord each resolves to.
| Chord type | Structure | Inversion options | Example (target = V in C major) |
|---|---|---|---|
| vii°6 | Diminished triad | First inversion only | F#-A-C in first inversion |
| vii°7 | Fully diminished seventh | Any inversion | F#-A-C-Eb |
| viiø7 | Half-diminished seventh | Any inversion | F#-A-C-E (major-key context) |
Part-writing secondary leading-tone chords follows the same rules as part-writing diatonic leading-tone chords. The temporary leading tone resolves up by half step to the root of the target chord, the chordal seventh resolves down by step, and you must avoid doubling any tendency tone. Watch carefully for parallel fifths and octaves when the diminished seventh resolves, since all four voices move simultaneously.
Write a four-voice resolution of vii°7/V in Bb major. Check: does the leading tone resolve up? Does the seventh resolve down? Are there any parallel fifths or octaves?
| Term | Definition |
|---|---|
| Secondary Dominants | Major triads or dominant seventh chords built on the fifth of a target chord, used to tonicize any major or minor triad in the key. Notated with a slash, such as V/V or V7/ii. |
| V/V | The secondary dominant of the dominant chord. In C major, V/V is D-F#-A; the F# is the chromatic alteration that creates a dominant pull toward G (V). |
| V/ii | A secondary dominant chord that tonicizes the ii chord of the primary key by acting as ii's own dominant, requiring a chromatic accidental to raise the temporary leading tone. |
| Dominant Function | The harmonic tendency of a dominant or leading-tone chord to resolve to a tonic. Secondary function chords borrow this tendency and aim it at a non-tonic chord. |
| Leading Tone Resolution | The tendency of a leading tone to resolve upward by half step to the tonic. In applied chords, the chromatic pitch acting as the temporary leading tone must resolve up to the root of the tonicized chord. |
| Chordal Seventh | The note a seventh above the root of a chord. In any secondary dominant or secondary leading-tone seventh chord, the chordal seventh must resolve down by step to the third of the target chord. |
| Roman numeral analysis | The system used to label chords by their scale-degree function. Applied chords use slash notation (e.g., vii°7/V) where the left side names the applied chord type and the right side names the target. |
| Modulation | A confirmed change of primary key, distinguished from tonicization by the presence of a cadence in the new key. Tonicization does not constitute modulation. |
| Harmonic Progressions | Sequences of chords that create movement and direction. Applied chords enrich progressions by introducing chromatic dominant-to-tonic motion aimed at non-tonic chords. |
| Stepwise Motion | Movement between adjacent scale degrees. The chordal seventh and temporary leading tone in applied chords both resolve by stepwise motion, down and up respectively. |
| Deceptive Resolution | A harmonic move in which an expected tonic resolution is replaced by a different chord. Secondary dominants can resolve deceptively just as diatonic dominants can. |
| Non-Chord Tone | A pitch that does not belong to the prevailing chord. Chromatic accidentals in applied chords are chord tones, not non-chord tones, and must be treated as tendency tones in voice leading. |
A single applied chord, or even a short string of them, does not constitute modulation. If there is no cadence confirming a new key, the primary key has not changed. Label the chord with slash notation rather than rewriting the key.
The raised pitch in an applied chord is a tendency tone and must not be doubled. Doubling it forces one voice to resolve incorrectly or creates parallel octaves. Double the root or fifth of the applied chord instead.
Secondary diminished triads follow the same rule as diatonic leading-tone triads: root position is avoided because it creates a diminished fifth above the bass. Always place the third of the chord in the bass when using the diminished triad form.
The seventh of any applied dominant or applied leading-tone seventh chord resolves down by step, not up. Moving it upward is a voice-leading error that will be flagged in error-detection tasks.
The Roman numeral to the right of the slash is the chord being tonicized, not the chord the applied chord is built on. V/V means a dominant chord that resolves to V, not a chord built on V.
The AP Music Theory exam regularly asks students to analyze passages containing chromatic chords and provide Roman numeral labels. For Unit 7 content, this means correctly identifying the applied chord type, the target chord, and any inversion, using slash notation with quality symbols (°, ø) and figured-bass numbers where required.
Free-response tasks may ask you to complete a four-voice progression that includes applied chords, or to identify specific voice-leading errors in a given passage. For secondary function chords, examiners look at whether the temporary leading tone resolves up, the chordal seventh resolves down, tendency tones are not doubled, and parallel perfect intervals are avoided.
Listening tasks may require you to identify tonicization by ear, distinguishing the chromatic pull of an applied chord from a diatonic progression or a full modulation. Recognizing the characteristic sound of V/V or vii°7/V resolving to a non-tonic chord, and noting the absence of a confirming cadence in a new key, are the key listening skills for this unit.
Unit 7 printables
Print the unit cheatsheets ($3) for Unit 7. Yours to keep, no subscription needed.
get printablesThe AP Music Theory Unit 7 progress check pulls questions from all four topics: secondary dominant chords, part writing of secondary dominants, secondary leading-tone chords, and part writing of secondary leading-tone chords. The MCQ portion tests your ability to identify tonicization and label secondary function chords in context. The FRQ portion typically asks you to realize or correct part writing that involves secondary dominants or secondary leading-tone chords. Practicing the progress check by topic is the most efficient approach. You can find practice questions matched to each Unit 7 topic at AP Music Theory Unit 7.
AP Music Theory Unit 7 FRQs focus on part writing secondary dominant chords and secondary leading-tone chords, so the best practice is writing out four-voice progressions that include a secondary dominant resolving to its temporary tonic. Topics 7.2 and 7.4 generate the most FRQ-style tasks: you'll be asked to realize a figured bass or correct voice-leading errors in a passage that uses tonicization. To build fluency, work through progressions that move from a secondary dominant (like V7/V) to its target chord, checking for proper resolution of the leading tone and seventh. Then try the same with diminished seventh chords from Topic 7.4. Practice sets are available at AP Music Theory Unit 7.
Start with tonicization as the core concept: a secondary dominant chord makes a non-tonic chord temporarily feel like a tonic, and that idea connects all four Unit 7 topics. Once that clicks, the part-writing rules for secondary dominants (Topic 7.2) and secondary leading-tone chords (Topic 7.4) will feel logical rather than arbitrary. A solid study sequence looks like this: 1. Learn to identify and label secondary dominant chords (V/V, V7/IV, etc.) by ear and on paper.
2. Practice resolving them correctly in four voices, paying close attention to the leading tone and chordal seventh.
3. Repeat steps 1 and 2 for secondary leading-tone chords, including diminished seventh chords.
4. Do timed part-writing drills that mix both chord types so you can switch between them quickly on the exam. Visit AP Music Theory Unit 7 for topic-by-topic practice to check your progress at each step.