Scientists used radioactive hydrogen to make water. They grew plants using the radioactive water. What happened to the radioactive hydrogen during photosynthesis?

Answer 1

6CO2 + 6H2O ==> C6H12O6 + 6O2
The radioactive hydrogen in the water is incorporated into the glucose formed during photosynthesis.
You may be asking about the radioactive 1H3. It decays to He via the following reaction. 1H3 ==> -1e0 + 2He3
The half-life of 1H3 or T is 12.3 years.

Answer 2

Hm. Ty. This is well appreciated.