Ortho position in organic chemistry is the one in which there are two same functional groups, tied to a ring of benzene in the positions 1 and 2. The abbreviation o- is used, for example, o-Hydroquinone is 1,2-dihydroxybenzene.
Generalic, Eni. "Ortho position." Croatian-English Chemistry Dictionary & Glossary. 29 June 2022. KTF-Split. {Date of access}. <https://glossary.periodni.com>.
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