Which one of the following equation suggests that `O_(2)` released during photosynthesis comes from water?

Options

A. `6CO_(2)^(18)+12H_(2)Orarr6O_(2)^(18)+C_(6)H_(12)O_(6)+6H_(2)O^(18)`
B. `6CO_(2)+12H_(2)O^(18)+rarr6O_(2)+C_(6)H_(12)O_(6)+6H_(2)O^(18)`
C. `6CO_(2)^(18)+12H_(2)Orarr6O_(2)^(18)+C_(6)H_(12)O_(6)+6H_(2)O`
D. `6CO_(2)+12H_(2)O^(!8)rarr6O_(2)^(18)+C_(6)H_(12)O_(6)+6H_(2)O`

Answer

D

Explanation

Ruben and Kamen (1741), whlile working on Chlorella (Unicellular green alga) found that oxygen liberated during photosynthesis comes from water.
(i) When normal `H_(2)O` and radioactive `CO_(2)(i.e. CO_(2)^(18))` were used, normal `O_92)` is evolved
(ii) When normal `CO_(2)` and radioactive `H_(2)O(ie.H_(2)O^(18))` were used, radioactive `O_(2)(i.e.O_(2)^(18))` is evolved.
`nCO_(2)+nH_(2)O^(18)rarr(CH_92)O)_(n)+O_(2)^(18)uparrow`
(radioactive oxygen) `+H_(2)O`