Question

oxygen is present in water then why we can't breathe if we are in water​

Answer 1

Because after reaction of H2 and O there properties changes. That's why we can't breathe oxygen dissolved organic in water. In addition to this our body is designed to breathe oxygen dissolved in air .

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Answer 2

We cannot breathe in water because our lungs do not have enough surface area to absorb enough oxygen from water and the lining in our lungs are adapted to handle air rather then water.

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