Semiheavy water

Chemical compound

Semiheavy water (HDO or HOD) is a naturally occurring chemical variant of water. Other variants include heavy water (D2O), and H2O. It shares most of its properties with common water (1H2O), with its distinguishing feature being a single hydrogen atom per water molecule being of the heavier isotope deuterium (2H or D), as opposed to the far more common protium (1H). This difference of one more neutron in one of the hydrogen atoms does not notably change its chemical properties, as these are mostly dictated by the number of valence electrons an atom has.

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