Question

why does a slice of a apple turn brown? ​

Answer 1

Answer:

due to iron

Explanation:

the iron present in apple makes the slice to turn brown

Answer 2

When an apple is injured (or cut into pieces), the plant tissue is exposed to oxygen.

This triggers an enzyme known as polyphenol oxidase (PPO) to—wait for it—oxidize polyphenols in the apple's flesh.

Thus, the slice of the apple turns brown.