C 7th chord

C7 chord for piano with keyboard diagram.
Explanation: The C seventh is a dominant four-note chord. You can see the four notes of the C seventh chord marked in red color. The chord is often abbreviated as C7.
Omissions: C7(no3): C - G - Bb; C7(no5): C - E - Bb.
Theory: The C seventh chord is constructed with a root, a major third, a perfect fifth and a minor seventh.
Fingerings: Little finger, middle finger, index finger, thumb (left hand); thumb, index finger, middle finger, little finger (right hand).

C7

Notes: C - E - G - Bb
Left hand: 5-3-2-1
Right hand: 1-2-3-5

C7 - inversions

Explanation: The images below show the three inversions of the C dominant seventh chord. C7/E is a C dominant seventh with E as the bass note, C7/G is a C dominant seventh with G as the bass note and C7/Bb is a C dominant seventh with Bb as the bass note.

C7/E

1st inversion

C7/G

2nd inversion

C7/Bb

3rd inversion