How could you describe the tonality of the exposition in Mozarts 42nd symphony (Jupiter) (First movement)?
well tonality is relating to the actual key of the piece, as opposed to harmony which is relating to the chords and chord progression, when talking about tonality be sure to mention anything to do with modulation, weather the key is properly established or not, the difference of being in a key and implying a key and weather the piece is just passing through a number of keys.