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  2. List of unsolved problems in chemistry - Wikipedia

    en.wikipedia.org/wiki/List_of_unsolved_problems...

    [13] Protein folding problem: Is it possible to predict the secondary, tertiary and quaternary structure of a polypeptide sequence based solely on the sequence and environmental information? Inverse protein-folding problem: Is it possible to design a polypeptide sequence which will adopt a given structure under certain environmental conditions?

  3. Dynamic kinetic resolution in asymmetric synthesis - Wikipedia

    en.wikipedia.org/wiki/Dynamic_Kinetic_Resolution...

    Dynamic kinetic resolution in chemistry is a type of kinetic resolution where 100% of a racemic compound can be converted into an enantiopure compound. It is applied in asymmetric synthesis . Asymmetric synthesis has become a much explored field due to the challenge of creating a compound with a single 3D structure. [ 1 ]

  4. Chemical reaction - Wikipedia

    en.wikipedia.org/wiki/Chemical_reaction

    Nuclear chemistry is a sub-discipline of chemistry that involves the chemical reactions of unstable and radioactive elements where both electronic and nuclear changes can occur. The substance (or substances) initially involved in a chemical reaction are called reactants or reagents.

  5. Phase transition - Wikipedia

    en.wikipedia.org/wiki/Phase_transition

    Phase transitions commonly refer to when a substance transforms between one of the four states of matter to another. At the phase transition point for a substance, for instance the boiling point, the two phases involved - liquid and vapor, have identical free energies and therefore are equally likely to exist.

  6. 1,3-Dipolar cycloaddition - Wikipedia

    en.wikipedia.org/wiki/1,3-Dipolar_cycloaddition

    Examples of substrate-controlled diastereoselective 1,3-dipolar cycloadditions are shown below. First is the reaction between benzonitrile N-benzylide and methyl acrylate . In the transition state, the phenyl and the methyl ester groups stack to give the cis -substitution as the exclusive final pyrroline product.

  7. Avrami equation - Wikipedia

    en.wikipedia.org/wiki/Avrami_equation

    The transformation can be described using the Avrami equation as a plot of ⁡ ⁡ vs ⁡, yielding a straight line. Transformations are often seen to follow a characteristic s-shaped, or sigmoidal, profile where the transformation rates are low at the beginning and the end of the transformation but rapid in between.

  8. Rotamer - Wikipedia

    en.wikipedia.org/wiki/Rotamer

    For example, the ΔG° for the transformation of butane from the gauche conformer to the anti conformer is −0.47 kcal/mol at 298 K. [13] This gives an equilibrium constant is about 2.2 in favor of the anti conformer, or a 31:69 mixture of gauche:anti conformers at equilibrium.

  9. Chemical energy - Wikipedia

    en.wikipedia.org/wiki/Chemical_energy

    Chemical energy is the energy of chemical substances that is released when the substances undergo a chemical reaction and transform into other substances. Some examples of storage media of chemical energy include batteries, [1] food, and gasoline (as well as oxygen gas, which is of high chemical energy due to its relatively weak double bond [2] and indispensable for chemical-energy release in ...