The first movement is written in sonata form. It is in the key of C major. The tempo marking is Allegro (Fast). The opening theme is accompanied by an Alberti bass played in the left hand. A bridge passage composed of scales follows, arriving at a cadence in G major, the key in which the second theme is then played. A codetta follows to conclude the exposition. The exposition is repeated. The development starts in G minor and modulates through several keys. The recapitulation begins in the subdominant key of F major. According to Charles Rosen, the practice of beginning a recapitulation in the subdominant was "rare at the time [the sonata] was written"..