Chord V7 – The Dominant 7th

Chord V7 – Dominant 7^th

The dominant chord (V) was introduced at grade 5. Chord V7 is also known as the “dominant 7^th” chord. It is built from the dominant triad, plus another third added on top: the 5^th, 7^th, 2^nd and 4^th notes of the scale.

In C major, the dominant 7^th chord contains the notes G, B, D and F.

In minor keys, the dominant 7^th is built from the harmonic minor scale.

In A minor, the dominant 7^th chord contains the notes E, G#, B and D.

Dominant 7ths are useful chords because they each only belong to one pair of keys, unlike triads, which can belong to several different keys. For this reason, chord V7 can help you to work out musical keys more easily. The pair of keys which a V7 chord belongs to is always the major and minor key a perfect 5^th lower.

For example, the chord of G7 belongs to the keys of C major and C minor (C is a perfect 5^th lower than G). It does not belong to any other key.

Dominant 7^th chords are also quite easy to spot, because they have a unique shape. They are the only chords which contain a major triad, plus a minor 7^th between the root and 7^th. If you see a four-note chord built in this way, then it must be a V7 chord.

V7 usually moves to chord I. Here is the end of the third movement of Mozart’s piano sonata no.1, K279, in C major. The dominant 7^th contains the notes G, B, D and F. There are several chord V7s, each moving on to chord I.