Do we take up identical amounts of oxygen to the amounts of CO2 that we output? Equivalently, do plants take up identical amounts of CO2 as they release O2? (moles, averaged over >24 hours)

I was interested in the contribution of room-plants in removal of (harmful) CO2. From theoretical knowledge of photosynthesis, the citric acid cycle and respiration chain, I suspect that a persons molar CO2 output is roughly identical to the O2 input, and in reverse for plants, as summarized by the net-equations:

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Diverse sources mention that human needs around 0.8 kg oxygen per day, while realistic house-plant acquisitions produce no more than 10% of that. Paradoxically, while the effect of house-plants in O2 production was described as minuscule, plants were consistently highlighted for their efficient removal of CO2 from rooms. (I know that the ratio of CO2 to O2 is around 1:20, so absolute removal of CO2 has higher relative effect.)

As I personally cannot exclude a contribution of human secretion (sweat, unary..), and also I lack knowledge of the exact chemical composition of molecules that are accumulated during plant growth and storage (in bulbs or fruits), which may contain different ratios of oxygen and carbon, I cannot exclude that in/-output O2/CO2 ratios can deviate from perfect equivalence. But if so, by how much?


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