are there piano pieces where the hands play in different keys?

Question

Do you know music for piano where the two hands don't have to play in the same key?

Answer 1

In general, music is viewed in one key based on its tonal center and place of resolution, and all other notes are viewed in relation to that key.

There can be a lot of ambiguous blending between relative major and minors, or any two keys with mostly common notes, but in general the primary tonal center (often used as the first and last chord) determines the one key of the piece.

Changing the primary key throughout the piece is also very common.

Answer 2

Playing in 2 different keys at the same time? Not really, unless you are going for some dissonant sound. However, songs quite often start in one key and then end with a big key change. I say "Big" as they often go with crescendos. And, the chorus of a song can be played in a different key than the rest of the song or the bridge etc. A good song writer can pull off just about anything. I hope this helps answer your question.