if u you leave it on a counter sliced then the bacteria grows on it causing it to get rotten and really gross, but if you leave it in a fridge then it will very slowly turn brown
Apples spoil because of the oxygen and if they don't get eaten they spoil
oxidation
It depends what temperature it's at, what kind it is or how old it is
Oxidation (Exposure to oxgen). This is what causes apples to turn brown.
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