[Right Wing Professor]

H2O is water H3O is heavy water and exists in bodies of H2O.

H₂O is water, and also heavy water. In ordinary water, the hydrogen atoms are almost entirely the light isotope of hydrogen, ¹H, occasionally called protium. In heavy water, they are a heavier isotope of hydrogen, ²H, also called deuterium. The chemical formula of both, however, is the same.

[jec41]

1H, occasionally called protium. In heavy water, they are a heavier isotope of hydrogen, 2H, also called deuterium. The chemical formula of both, however, is the same.

Thanks professor for pointing out my error. It would not be my intention to mislead anyone by a misstatement of a fact. In my haste to reply it was simply a case of open mouth and insert foot without reviewing my recollection of chemistry studied 45 years past. In retrospect I learned it 2H2O. Heavy water and semi heavy water were only discovered a short time before my birth and mine was not a in depth study.