Ah, the never-ending grammar battle of which word to use. Piece and peace are homonyms, but they mean totally different things.
The word piece means part of a whole.
The word peace means freedom from war, or tranquility. I’m sure most people know the differences between the meanings, but many people spell one when they mean the other.
An easy way to remember which one you need and how to spell it: piece has an “I” in it; and piece begins with the letters p-i-e, so if you remember I took a piece of pie, then that should help your memory. Peace has an "a" in it, and when you have peace and quiet, you want to say "aaaaahhhhhh."