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  2. List of unsolved problems in chemistry - Wikipedia

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

    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. Base (chemistry) - Wikipedia

    en.wikipedia.org/wiki/Base_(chemistry)

    A strong base is a basic chemical compound that can remove a proton (H +) from (or deprotonate) a molecule of even a very weak acid (such as water) in an acid–base reaction. Common examples of strong bases include hydroxides of alkali metals and alkaline earth metals, like NaOH and Ca(OH) 2, respectively. Due to their low solubility, some ...

  4. Superbase - Wikipedia

    en.wikipedia.org/wiki/Superbase

    Caubère defines superbases as "bases resulting from a mixing of two (or more) bases leading to new basic species possessing inherent new properties. The term superbase does not mean a base is thermodynamically and/or kinetically stronger than another, instead it means that a basic reagent is created by combining the characteristics of several ...

  5. Leveling effect - Wikipedia

    en.wikipedia.org/wiki/Leveling_effect

    For example, aqueous perchloric acid (HClO 4), aqueous hydrochloric acid (HCl) and aqueous nitric acid (HNO 3) are all completely ionized, and are all equally strong acids. [ 3 ] Similarly, when ammonia is the solvent, the strongest acid is ammonium (NH 4 + ), thus HCl and a super acid exert the same acidifying effect.

  6. Proton affinity - Wikipedia

    en.wikipedia.org/wiki/Proton_affinity

    The higher the proton affinity, the stronger the base and the weaker the conjugate acid in the gas phase.The (reportedly) strongest known base is the ortho-diethynylbenzene dianion (E pa = 1843 kJ/mol), [3] followed by the methanide anion (E pa = 1743 kJ/mol) and the hydride ion (E pa = 1675 kJ/mol), [4] making methane the weakest proton acid [5] in the gas phase, followed by dihydrogen.

  7. Weak base - Wikipedia

    en.wikipedia.org/wiki/Weak_base

    An example of a weak base is ammonia. It does not contain hydroxide ions, but it reacts with water to produce ammonium ions and hydroxide ions. [4] The position of equilibrium varies from base to base when a weak base reacts with water. The further to the left it is, the weaker the base. [5]

  8. Acid–base reaction - Wikipedia

    en.wikipedia.org/wiki/Acid–base_reaction

    In chemistry, an acid–base reaction is a chemical reaction that occurs between an acid and a base.It can be used to determine pH via titration.Several theoretical frameworks provide alternative conceptions of the reaction mechanisms and their application in solving related problems; these are called the acid–base theories, for example, Brønsted–Lowry acid–base theory.

  9. Henderson–Hasselbalch equation - Wikipedia

    en.wikipedia.org/wiki/Henderson–Hasselbalch...

    A simple buffer solution consists of a solution of an acid and a salt of the conjugate base of the acid. For example, the acid may be acetic acid and the salt may be sodium acetate . The Henderson–Hasselbalch equation relates the pH of a solution containing a mixture of the two components to the acid dissociation constant , K a of the acid ...