Why does a lump of cotton wool shrink in water?

Why does a lump of cotton wool shrink in water? 

Grade:upto college level

4 Answers

askIITians Faculty 33 Points
8 years ago
The lump of cotton has air filled in it. Once its dipped in water, this air is released and the lump shrinks.

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Dinesh Sajnani
AskIITians Faculty
733 Points
8 years ago
A lump of cotton wool shrinks in water because water filled up the empty space that the air has occupied.
Ritika Das
105 Points
6 years ago
Before the cotton wool has been soaked in the water and was completely dry, there were enough spaces inside the cotton containing air just like in sponge. When dipped in water, the air can no more occupy the space and therefore it shrinks compared to being fluffier before and gains weight.
111 Points
5 years ago
Lump of Cotton wool when dipped in water shrinks because of the presence of air between the gaps of cotton fibre.
When it is dipped, the water replaces air from those gaps, making the cotton lump heavy and it finally shrinks as the air gaps are removed.

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