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  2. Iodine clock reaction - Wikipedia

    en.wikipedia.org/wiki/Iodine_clock_reaction

    The iodine clock reaction is a classical chemical clock demonstration experiment to display chemical kinetics in action; it was discovered by Hans Heinrich Landolt in 1886. [1] The iodine clock reaction exists in several variations, which each involve iodine species ( iodide ion, free iodine, or iodate ion) and redox reagents in the presence of ...

  3. Fractional crystallization (chemistry) - Wikipedia

    en.wikipedia.org/wiki/Fractional_crystallization...

    In chemistry, fractional crystallization is a stage-wise separation technique that relies on the liquid–solid phase change. This technique fractionates via differences in crystallization temperature and enables the purification of multi-component mixtures, as long as none of the constituents can act as solvents to the others.

  4. Mathematics of three-phase electric power - Wikipedia

    en.wikipedia.org/wiki/Mathematics_of_three-phase...

    For example, balanced two-phase power can be obtained from a three-phase network by using two specially constructed transformers, with taps at 50% and 86.6% of the primary voltage. This Scott T connection produces a true two-phase system with 90° time difference between the phases.

  5. Reaction mechanism - Wikipedia

    en.wikipedia.org/wiki/Reaction_mechanism

    In chemistry, a reaction mechanism is the step by step sequence of elementary reactions by which overall chemical reaction occurs. [1]A chemical mechanism is a theoretical conjecture that tries to describe in detail what takes place at each stage of an overall chemical reaction.

  6. Protocol (science) - Wikipedia

    en.wikipedia.org/wiki/Protocol_(science)

    In natural and social science research, a protocol is most commonly a predefined procedural method in the design and implementation of an experiment.Protocols are written whenever it is desirable to standardize a laboratory method to ensure successful replication of results by others in the same laboratory or by other laboratories.

  7. Electrochemical stripping analysis - Wikipedia

    en.wikipedia.org/wiki/Electrochemical_stripping...

    Electrochemical stripping analysis is a set of analytical chemistry methods based on voltammetry [1] or potentiometry [2] that are used for quantitative determination of ions in solution. [3] Stripping voltammetry (anodic, cathodic and adsorptive) have been employed for analysis of organic molecules as well as metal ions.

  8. Crystallization - Wikipedia

    en.wikipedia.org/wiki/Crystallization

    Crystallization occurs in two major steps. The first is nucleation, the appearance of a crystalline phase from either a supercooled liquid or a supersaturated solvent. The second step is known as crystal growth, which is the increase in the size of particles and leads to a crystal state. An important feature of this step is that loose particles ...

  9. Direct methods (crystallography) - Wikipedia

    en.wikipedia.org/wiki/Direct_methods...

    In crystallography, direct methods are a family of methods for estimating the phases of the Fourier transform of the scattering density from the corresponding magnitudes. . The methods generally exploit constraints or statistical correlations between the phases of different Fourier components that result from the fact that the scattering density must be a positive real nu