Mozart’s Sonata No. 8 in A minor, K. 310, opens with an Allegro maestoso whose firm dotted rhythm and repeated accompaniment chords give it an unusually insistent character. The right hand begins with a clearly accented melodic statement, while the left hand supplies a nearly continuous pulse of eighth-note chords. This compact opening soon expands into long running passages, changing registers, and exchanges between the two hands. The movement brings its opening material back after an unsettled middle section and closes forcefully in A minor.

In the opening section, short slurred melodic gestures sit above closely repeated chords. The contrast between the dotted melody and the even accompaniment remains audible as the harmony moves forward. Fast sixteenth notes then loosen the texture, with a held upper or inner note sometimes continuing while another line moves underneath. The following material gives the right hand extended scales and turning figures against detached left-hand chords, before the bass becomes more sustained and independent.

The latter part of the exposition transfers much of the rapid movement to the left hand. Above its running sixteenths, the right hand places widely separated notes, octave shapes, and trills. The closing idea brings back the dotted rhythm in a more chordal texture, building through stronger dynamics to a fortissimo cadence. A repeat sign sends the player back through this opening portion before the music continues into the development.

The middle section begins by reshaping the dotted theme over repeated chords in changing harmonies. Sharps, flats, and naturals appear frequently as the music moves through contrasting tonal areas. Later, the left hand maintains rapid broken figures beneath upper notes that move at different speeds. Trills and running lines pass between the registers, and the printed dynamics range from very quiet passages to emphatic fortissimo statements.

When the main theme returns, its repeated accompaniment and accented rhythm restore the opening character. The following passages include quick figures spanning octave positions, renewed running sixteenths, and ornamental cadences. Near the end, the hands answer one another with descending runs and strong chords. The dotted closing idea then gathers weight through a crescendo and ends with decisive A-minor chords and octaves.

Interesting fact: The rapid accompaniment changes hands within this movement. Extended right-hand sixteenth-note passages are answered by passages in which the left hand carries the continuous motion beneath a more widely spaced upper line.