The water having more dissolved O2 is :
Solution
On heating concentration of O<sub>2</sub> in water decreases. So boiling water and water at 80$^\circ$C having less O<sub>2</sub> concentration. Polluted water also having less O<sub>2</sub> concentration. So water at 4$^\circ$C having maximum O<sub>2</sub> concentration.
About this question
Subject: Chemistry · Chapter: p-Block Elements · Topic: Group 13: Boron Family
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