Question

why do cut fruits take up a brown colour when exposed to air

Answer 1

because usually fruits contain iron and when it reacts with air or oxygen then it turns brown...

Answer 2

Apples and other fruit turn brown once the cut surface is exposed to air due to a reaction with oxygen in the surrounding air, a chemical reaction called oxidation. (Advanced: Some fruits contain enzymes that facilitate oxidation and coloration of the fruit when exposed to air..

I THINK YOU WILL BETTER UNDERSTAND BY SEEING PIC .... SEE ABOVE .... THE PIC

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