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orthohydrogen

American  
[awr-thuh-hahy-druh-juhn] / ˌɔr θəˈhaɪ drə dʒən /

noun

Physics, Chemistry.
  1. the form of molecular hydrogen in which the nuclei of the two hydrogen atoms contained in the molecule have spins in the same direction.


orthohydrogen British  
/ ˌɔːθəʊˈhaɪdrədʒən /

noun

  1. chem the form of molecular hydrogen, constituting about 75 per cent of the total at normal temperatures, in which the nuclei of the atoms spin in the same direction Compare parahydrogen

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Etymology

Origin of orthohydrogen

First recorded in 1925–30; ortho- + hydrogen

Example Sentences

Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.

Orthohydrogen and parahydrogen, two different kinds of hydrogen molecules having electrons revolving in different directions, discovered.

From Time Magazine Archive

That was proof that he had two different kinds of hydrogen, which he called orthohydrogen and parahydrogen.

From Time Magazine Archive

“Indeed,” he rambled on, “Treadmore babbled for Heaven knows how long on the relative occurrence of parahydrogen and orthohydrogen on Eisberg.”

From Project Gutenberg