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  2. General chemistry - Wikipedia

    en.wikipedia.org/wiki/General_chemistry

    General chemistry professors have been known to make tests worth a large portion of the course, and make them more challenging than the material presents itself as. Grade deflation, purposely adjusting the grades of a course to be lower, is also an issue of general chemistry courses at the undergraduate level.

  3. List of unsolved problems in chemistry - Wikipedia

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

    In 2020, it was announced that Google's AlphaFold, a neural network based on DeepMind artificial intelligence, is capable of predicting a protein's final shape based solely on its amino-acid chain with an accuracy of around 90% on a test sample of proteins used by the team.

  4. Chemistry - Wikipedia

    en.wikipedia.org/wiki/Chemistry

    Chemistry is the scientific study of the properties and behavior of matter. [1] It is a physical science within the natural sciences that studies the chemical elements that make up matter and compounds made of atoms, molecules and ions: their composition, structure, properties, behavior and the changes they undergo during reactions with other substances.

  5. Debye–Hückel theory - Wikipedia

    en.wikipedia.org/wiki/Debye–Hückel_theory

    Section 2.4.2 D&H say that this approximation holds at large distances between ions, [21]: 227 which is the same as saying that the concentration is low. Lastly, they claim without proof that the addition of more terms in the expansion has little effect on the final solution.

  6. Reformatsky reaction - Wikipedia

    en.wikipedia.org/wiki/Reformatsky_reaction

    The crystal structures of the THF complexes of the Reformatsky reagents tert-butyl bromozincacetate [25] and ethyl bromozincacetate [26] have been determined. Both form cyclic eight-membered dimers in the solid state, but differ in stereochemistry: the eight-membered ring in the ethyl derivative adopts a tub-shaped conformation and has cis bromo groups and cis THF ligands, whereas in the tert ...

  7. Ideal gas - Wikipedia

    en.wikipedia.org/wiki/Ideal_gas

    An ideal gas is a theoretical gas composed of many randomly moving point particles that are not subject to interparticle interactions. [1] The ideal gas concept is useful because it obeys the ideal gas law, a simplified equation of state, and is amenable to analysis under statistical mechanics.

  8. Hell–Volhard–Zelinsky halogenation - Wikipedia

    en.wikipedia.org/wiki/Hell–Volhard–Zelinsky...

    An example of the Hell–Volhard–Zelinsky reaction can be seen in the preparation of alanine from propionic acid.In the first step, a combination of bromine and phosphorus tribromide is used in the Hell–Volhard–Zelinsky reaction to prepare 2-bromopropionic acid, [3] which in the second step is converted to a racemic mixture of the amino acid product by ammonolysis.

  9. Acid–base titration - Wikipedia

    en.wikipedia.org/wiki/Acid–base_titration

    HCl + NaOH → NaCl + H 2 O. Acidimetry is the specialized analytical use of acid-base titration to determine the concentration of a basic (alkaline) substance using standard acid. This can be used for weak bases and strong bases. [8] An example of an acidimetric titration involving a strong base is as follows: Ba(OH) 2 + 2 H + → Ba 2+ + 2 H 2 O