Before we get to diatonic chords, let’s review the C Major scale and scale degrees.

First on the treble staff with scale degree numbers… 

Now on the treble staff with scale degree names…

So as you can see…

1 is tonic or root note

2 is supertonic

3 is mediant

4 is subdominant

5 is dominant

6 is submediant

7 is leading tone 

And then back to the tonic or root.

Now lets see what that would look like on the piano highlighted below first by note letter then by scale degree number…

Now that we have reviewed and established the names of the notes and scale degrees of the C Major scale, we can build simple triad chords off each note. Triad meaning 3 note chords.  Let’s start with the note C and work our way up the scale. These are called diatonic chords and every major scale has them…

Every note off the C Major Scale can be built into 3 note triad chords.

CEG is a C Major Chord aka the I Chord

DFA is a D minor Chord aka the ii Chord

EGB is an E minor Chord aka the iii Chord

FAC is a F Major Chord aka the IV Chord

GBD is a G Major Chord aka the V Chord

ACE is an A minor Chord aka the vi Chord

BDF is a diminished triad aka the vii Chord (more diminished stuff later)

CEG is a C Major Chord aka the I Chord 

Until next time your assignment is to find these diatonic triads in C Major on your piano keyboard.  Once you’ve done that then do it for all 12 Major Scales…