Chord I, C major consists of the notes, C – E – G
Chord ii, D minor consists of the notes, D – F – A
Chord iii, E minor contains the notes, E – G – B
Chord IV, F major contains the notes, F – A – C
Chord V, G major contains the notes, G – B – D
Chord vi, A minor consists of the notes, A – C – E
Chord vii°, B diminished consists of the notes, B – D – F.
For example, the chords of the C major scale:
Chord I, C major consists of the notes, C – E – G Chord ii, D minor consists of the notes, D – F – A Chord iii, E minor contains the notes, E – G – B Chord IV, F major contains the notes, F – A – C Chord V, G major contains the notes, G – B – D Chord vi, A minor consists of the notes, A – C – E Chord vii°, B diminished consists of the notes, B – D – F.