C#
C natural
Chords don't have "tonic notes". Scales do. The tonic note of the G major scale is G (in fact, the tonic note of the X major/minor scale will always be X). Chords do have roots, but that's equally boring: the root of the G major chord is G.
Each scale has a Leading Tone (which is the 7th note of the scale) and a Tonic Note (which is the first/eighth note of the scale). For the key of C major, the leading tone would be B, and the tonic note would be C.
Relative major and minor share the same key signature but a different tonic note (a tonic note is the first note of the scale or in solfege tonic is DO). For example, D flat major has five flats in it's key signature and b flat minor has 5 flats in it's key signature; therefore, D flat major and b flat minor are relative.
The tonic of C major is the note C itself. In music theory, the tonic is the first note of a scale and serves as the home or reference note around which the other notes in the scale are organized. In the context of C major, the scale consists of the notes C, D, E, F, G, A, and B.
It is a major chord. Actually, tonic is simply defined as the first note in the scale or key. All chords have tonic note. The tonic of a C chord is the C. The tonic of a C minor chord is a C. The tonic of a C minor major 7 is a C.
The supertonic triad in the key of A flat major is B flat, D flat, and F natural
b major
The tonic of E flat major is E flat. Its dominant is B flat and its subdominant is A flat.
The first note of a musical scale depends on the key you're in. For instance, if you're in the key of A, the first note, known as the root, would be A. If you're in the key of F#, the root would be F#. No matter if you're playing the major scale, the minor scale, the blues scale, or any other scale, the root always matches the chord you're playing over.
Generally, the leading note is the seventh tonal degree of the diatonic scale leading up to the tonic. For example, in the C major scale (white keys on a piano, starting on C), the leading note is the note B; and the leading note chord uses the notes B, D, and F: a diminished triad. In Music Theory, the leading note triad is symbolized by the Roman numeral vii°.
The leading note of B major is A#.