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  2. Woodward–Hoffmann rules - Wikipedia

    en.wikipedia.org/wiki/Woodward–Hoffmann_rules

    Thermolysis converts 1 to (E,E) geometric isomer 2, but 3 to (E,Z) isomer 4.. The Woodward–Hoffmann rules (or the pericyclic selection rules) [1] are a set of rules devised by Robert Burns Woodward and Roald Hoffmann to rationalize or predict certain aspects of the stereochemistry and activation energy of pericyclic reactions, an important class of reactions in organic chemistry.

  3. Optical rotation - Wikipedia

    en.wikipedia.org/wiki/Optical_rotation

    In case of optically active isotropic media, the rotation is the same for any direction of wave propagation. In contrast, the Faraday effect is non-reciprocal, i.e. opposite directions of wave propagation through a Faraday medium will result in clockwise and anti-clockwise polarization rotation from the point of view of an observer.

  4. Circular polarization - Wikipedia

    en.wikipedia.org/wiki/Circular_polarization

    It would be considered right-handed/clockwise circularly polarized if defined from the point of view of the receiver. Circular polarization may be referred to as right-handed or left-handed, and clockwise or anti-clockwise, depending on the direction in which the electric field vector rotates. Unfortunately, two opposing historical conventions ...

  5. Specific rotation - Wikipedia

    en.wikipedia.org/wiki/Specific_rotation

    The CRC Handbook of Chemistry and Physics defines specific rotation as: For an optically active substance, defined by [α] θ λ = α/γl, where α is the angle through which plane polarized light is rotated by a solution of mass concentration γ and path length l.

  6. Polarimeter - Wikipedia

    en.wikipedia.org/wiki/Polarimeter

    The optical activity of enantiomers is additive. If different enantiomers exist together in one solution, their optical activity adds up. That is why racemates are optically inactive, as they nullify their clockwise and counter clockwise optical activities. The optical rotation is proportional to the concentration of the optically active ...

  7. Clockwise - Wikipedia

    en.wikipedia.org/wiki/Clockwise

    Clockwise motion (abbreviated CW) proceeds in the same direction as a clock's hands relative to the observer: from the top to the right, then down and then to the left, and back up to the top. The opposite sense of rotation or revolution is (in Commonwealth English ) anticlockwise ( ACW ) or (in North American English ) counterclockwise ( CCW ...

  8. Clock position - Wikipedia

    en.wikipedia.org/wiki/Clock_position

    The clock system is easily converted into a 360 degree system for more precise denotation. One bearing, or point, is termed an azimuth. [2] The convention is that of analytic geometry: the y-axis at zero degrees is the longitudinal axis of the vehicle. Angles grow larger in the clockwise direction. Thus, directly to port is at 270 degrees.

  9. Glossary of chemistry terms - Wikipedia

    en.wikipedia.org/wiki/Glossary_of_chemistry_terms

    Also acid ionization constant or acidity constant. A quantitative measure of the strength of an acid in solution expressed as an equilibrium constant for a chemical dissociation reaction in the context of acid-base reactions. It is often given as its base-10 cologarithm, p K a. acid–base extraction A chemical reaction in which chemical species are separated from other acids and bases. acid ...