The dominant 7th chord plays an essential role in music, it is, along with Major and minor chords, one of the three pillars of harmony. Its notes are represented by the scale degrees 1, 3, 5, and 7♭. The flat 7 in a dominant 7th chord creates a form of tension. This is explained by the unstable nature of the intervals that compose it: the minor seventh between 1 and 7♭, as well as the interval called the 'tritone' (three tones) between 3 and 7♭.
Identify whether a chord is a dominant 7th chord. This exercise will help deepen your perception of the affects (emotional coloring) in music.
To master this exercise, remember to draw on the skills acquired in recognizing stable and unstable musical elements. We also recommend exploring for yourself, preferably on a keyboard, the different emotional qualities of two notes played simultaneously.