The equation for photosynthesis is:

[tex]\[ 6 H_2 O \text{ (water) } + 6 CO_2 \text{ (carbon dioxide) } + \text{Light Energy} \rightarrow C_6 H_{12} O_6 \text{ (glucose) } + 6 O_2 \text{ (oxygen)}. \][/tex]

When first discovered, scientists were trying to decide if the oxygen in the product came from carbon dioxide or water. Which statement describes how scientists traced the path of oxygen?

A. They used a radioactive isotope and tracked it with a Becquerel counter.
B. They used a radioactive isotope and tracked it with a Geiger counter.
C. They used a stable isotope and tracked it with a Becquerel counter.
D. They used a stable isotope and tracked it with a Geiger counter.



Answer :

Scientists used a radioactive isotope and tracked it with a Geiger counter to determine the source of the oxygen in the photosynthesis process. This method allowed them to trace the path of the oxygen atoms accurately by measuring the radiation emitted by the isotope, which is detected by the Geiger counter. The experiment revealed that the oxygen produced during photosynthesis comes from water (H₂O), not from carbon dioxide (CO₂).