The cut side gets exposed do the oxygen in the air and starts to react. Polyphenols are oxidised by oxygen from air when the 'polyphenol oxidase' enzyme is freed after cellular disruption (damage).
So the browning of cut apples is oxidation - the same as rust. Potatoes, apples and avocados to name a few do it. if you squeeze lemon juice on avocados, and put potatoes and apples in acidulated water (water with lemon juice) they won't oxidize.
A different thought...
It rots. The apple has been decomposed. So the answer would be decomposition.
A apple
It changes chemically.
Penis
it is changed to a clay form
You get hash browns.
Nothing. Popping is a physical change.
Helium is chemically inert and does not react with aluminium
Applesauce- instant! The apple blows apart.
It will turn into a rooten apple.
The apple turns brown and loses color.
sodium and chlorine (Na and Cl) chemically combine
When you heat sulphar you chemically mix it with oxygen therefore creating sulphide