Question

what is source of oxygen in atmosphere !?

Answer 1

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1. Early in the earth's history, oxygen is thought to have been emitted by UV radiation from water vapor and deposited in the atmosphere while the hydrogen fled into the earth's outer atmosphere.

2. The principal driving force of the oxygen cycle in which water and carbon dioxide combine through photosynthesis process in the presence of sunlight to form glucose.

3. Molecular oxygen is primarily found in the minerals and rocks.

4. The organism-led weathering cycle can also release the oxygen from the lithosphere.

5. Plants and animals remove nutrient minerals from rocks, and in the process release oxygen.