Search results
Results from the WOW.Com Content Network
At last count 96/97 of the 97 elements (hydrogen through einsteinium, except astatine and francium) isolated in pure form and in macroscopic quantities have images.; There are few images of very low encyclopedic quality for which it should be relatively easy to obtain higher quality: Ca.
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?
Relative volatility is a measure comparing the vapor pressures of the components in a liquid mixture of chemicals. This quantity is widely used in designing large industrial distillation processes. [ 1 ] [ 2 ] [ 3 ] In effect, it indicates the ease or difficulty of using distillation to separate the more volatile components from the less ...
The composition of a non-stoichiometric compound usually varies in a continuous manner over a narrow range. Thus, the formula for wüstite is written as Fe 1−x O, where x is a small number (0.05 in the previous example) representing the deviation from the "ideal" formula. [3]
Raman spectroscopy is used in chemistry to identify molecules and study chemical bonding and intramolecular bonds. Because vibrational frequencies are specific to a molecule's chemical bonds and symmetry (the fingerprint region of organic molecules is in the wavenumber range 500–1,500 cm −1), [20] Raman provides a fingerprint to identify ...
where E binding is the binding energy (BE) of the electron measured relative to the chemical potential, E photon is the energy of the X-ray photons being used, E kinetic is the kinetic energy of the electron as measured by the instrument and is a work function-like term for the specific surface of the material, which in real measurements ...
In physical chemistry, the Arrhenius equation is a formula for the temperature dependence of reaction rates.The equation was proposed by Svante Arrhenius in 1889, based on the work of Dutch chemist Jacobus Henricus van 't Hoff who had noted in 1884 that the Van 't Hoff equation for the temperature dependence of equilibrium constants suggests such a formula for the rates of both forward and ...
The resulting electron configuration can be described in terms of bond type, parity and occupancy for example dihydrogen 1σ g 2. Alternatively it can be written as a molecular term symbol e.g. 1 Σ g + for dihydrogen. Sometimes, the letter n is used to designate a non-bonding orbital. For a stable bond, the bond order defined as