enow.com Web Search

Search results

  1. Results from the WOW.Com Content Network
  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. Conversion (chemistry) - Wikipedia

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

    Conversion and its related terms yield and selectivity are important terms in chemical reaction engineering.They are described as ratios of how much of a reactant has reacted (X — conversion, normally between zero and one), how much of a desired product was formed (Y — yield, normally also between zero and one) and how much desired product was formed in ratio to the undesired product(s) (S ...

  4. Wohl degradation - Wikipedia

    en.wikipedia.org/wiki/Wohl_degradation

    The Wohl degradation in carbohydrate chemistry is a chain contraction method for aldoses. [1] The classic example is the conversion of glucose to arabinose as shown below. The reaction is named after the German chemist Alfred Wohl (1863–1939).

  5. Yield (chemistry) - Wikipedia

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

    The yield coefficient is defined as the amount of cell mass (kg) or product formed (kg,mol) [Notes 1] related to the consumed substrate (carbon or nitrogen source or oxygen in kg or moles) or to the intracellular ATP production (moles)." [4] [5]: 168

  6. Nuclear transmutation - Wikipedia

    en.wikipedia.org/wiki/Nuclear_transmutation

    The term transmutation dates back to alchemy.Alchemists pursued the philosopher's stone, capable of chrysopoeia – the transformation of base metals into gold. [3] While alchemists often understood chrysopoeia as a metaphor for a mystical or religious process, some practitioners adopted a literal interpretation and tried to make gold through physical experimentation.

  7. 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.

  8. Reversible reaction - Wikipedia

    en.wikipedia.org/wiki/Reversible_reaction

    So, when the free energy change is large (more than about 30 kJ mol −1), the equilibrium constant is large (log K > 3) and the concentrations of the reactants at equilibrium are very small. Such a reaction is sometimes considered to be an irreversible reaction, although small amounts of the reactants are still expected to be present in the ...

  9. Equivalent (chemistry) - Wikipedia

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

    The solution has 1 mole or 1 equiv Na +, 1 mole or 2 equiv Ca 2+, and 3 mole or 3 equiv Cl −. An earlier definition, used especially for chemical elements , holds that an equivalent is the amount of a substance that will react with 1 g (0.035 oz) of hydrogen , 8 g (0.28 oz) of oxygen , or 35.5 g (1.25 oz) of chlorine —or that will displace ...