Chemistry Dictionary & Glossary: Terms Starting with O OBSERVABLEOCCLUSIONOCTAHEDRALOCTANE NUMBEROCTET RULEODD BOFF-AXIS CHROMATIC ABERRATIONOHM'S LAWOILOPEN SEXTETOPPERMAN SOURCEOPTIC AXISOPTICAL ACTIVITYOPTICAL ISOMERSORBITALORDINARY RAYOREORGANICORGANIC CHEMISTRYORGANIC COMPOUNDOSMOSISOSMOTIC PRESSUREOSTWALD PROCESSOSTWALD RIPENINGOUTER ORBITAL COMPLEXOVERLAPOXIDATIONOXIDATION NUMBEROXIDATION NUMBERSOXIDATION-REDUCTION REACTIONSOXIDEOXIDIZING AGENTOXYGEN-FREE HIGH-CONDUCTIVITY COPPER (OFHC)