Mozart's Piano Sonata in C Major First movement.
Exposition m. 1- 28
First Theme- m. 1-12 C Major
Transition - m. 13
Second Theme - m. 14-25 G Major
Codetta - m. 26-28
Development m. 29-41 harmonically unstable.
Recapitulation m. 42- 73
First Theme - m. 42- 57 F Major transitions back to C Major through runs
Transition - m. 58
Second Theme - m. 59- 70 C Major with some moments in D Major
Coda - m. 71-73
SONATA FORM!!! Well thank goodness this is a textbook example of a song written in sonata form. It is very clear cut in each section, with a clear exposition, development and recapitulation. The two themes are clearly divided by strong cadences and a one measure transition. The development section brings back motives from the second theme and then, well, develops upon them in a harmonically unstable way. The recapitulation brings back the themes of the exposition but this time they are in different keys. The first theme is in F Major, all though it ends in the expected key, C Major. The second theme seems to begin with C Major and then toy around with D major for a while. This is different from the first time around, but should because this is going to be the end of the piece so we need to end in tonic. The recapitulation of the second theme is followed by another coda which concludes this movement. The motive found in the second theme that seems important to me is the use of the falling broken chords. It is this same idea that is repeated and then explored in the development section, but instead of a broken chord, it is a run, with added accidentals.