Questions: Dominant Seventh Chords and Resolution

Question 1

In the V7 chord in C major (G–B–D–F), which two notes form the tritone that drives its powerful resolution to I?

• A. G and D (the root and fifth)
• B. B and F (the third and seventh)
• C. G and B (the root and third)
• D. D and F (the fifth and seventh)

Answer: (B)

The tritone in a V7 chord is between the third (the leading tone, B in C major) and the seventh (F). B is a half step below the tonic C; F is a half step above the third of I (E). These two notes resolve inward by contrary-motion half steps — B moves up to C, F moves down to E — landing precisely on notes of the I chord. This double convergence is the source of the V7's uniquely strong pull. G and D are stable consonances that don't carry the same dissonant urgency.

Question 2

A student insists that V7 chords must always resolve to the I chord because that is 'the rule.' A classmate disagrees, citing secondary dominants. Who is correct?

• A. The first student — V7 always resolves to I by definition in tonal music
• B. The classmate — a secondary dominant like V7/IV uses the same chord quality but resolves to IV, temporarily tonicizing it
• C. Neither — V7 chords are unstable and can resolve to any chord
• D. The first student — any non-I resolution violates the rules of functional harmony

Answer: (B)

The V7 quality (major triad + minor seventh) creates a tritone between the third and seventh, and that tritone resolves to the local tonic — whatever chord the V7 is pointing toward. In C major, V7/IV (A–C#–E–G) resolves to IV (F–A–C) by the same tritone logic. The leading-tone-like pull is real, but the destination is determined by context, not a fixed rule. Secondary dominants allow composers to strengthen any chord in the progression by approaching it with its own dominant seventh.

Question 3

In a V7–I resolution, the leading tone (third of V7) moves up by a half step to the tonic, while the seventh of V7 simultaneously moves down by a half step — two voices converging by contrary motion onto the I chord.

• T. True
• F. False

Answer: True

This is precisely what makes the V7 resolution so compelling. In C major: B (leading tone) is a half step below C (tonic of I) and moves upward; F (seventh) is a half step above E (third of I) and moves downward. These two contrary-motion half-step resolutions happen simultaneously, and their destination notes are the tonic and the third of I. No other chord in the key creates this kind of double gravitational pull toward the home chord.

Question 4

The dominant seventh chord's strong pull toward resolution comes primarily from having four notes rather than three — any four-note chord creates comparable tension.

• T. True
• F. False

Answer: False

The tension is not from the number of notes but from the tritone specifically formed between the third and seventh of the V7. The tritone (three whole steps, exactly half an octave) is the most dissonant interval in tonal music and demands resolution. Many four-note chords (such as major seventh chords or added-sixth chords) are quite stable and do not create the same urgency. The V7's power is structural: it places the tritone on the two scale degrees (the leading tone and the seventh) that have the strongest directional pull.

Question 5

Why does the tritone in a V7 chord resolve so compellingly to the I chord? Explain in terms of voice leading, not just as a rule.

Model answer: The tritone between the leading tone (e.g., B in C major) and the chord seventh (F) resolves because each note is only a half step away from a note in the tonic triad. B, one half step below C, has strong melodic pull upward; F, one half step above E, has strong melodic pull downward. When both voices resolve simultaneously in contrary motion — B up to C and F down to E — they land on the tonic and third of the I chord, creating a sense of double arrival and harmonic closure.

The explanation should go beyond 'it's the rule' to identify the mechanics: two voices in contrary-motion half-step resolution, each acting under the principle that small intervals create melodic pull toward resolution. The V7's power is that it activates this pull in two voices at once, making the I chord feel like the only possible destination. Understanding this mechanism also explains secondary dominants: any chord can feel like a local tonic if it is approached by a chord with the same tritone-resolution logic.