Search results
Results from the WOW.Com Content Network
A single-displacement reaction, also known as single replacement reaction or exchange reaction, is an archaic concept in chemistry. It describes the stoichiometry of some chemical reactions in which one element or ligand is replaced by atom or group. [1] [2] [3] It can be represented generically as: + +
In the first definitive book on defence mechanisms, The Ego and the Mechanisms of Defence (1936), [9] Anna Freud enumerated the ten defence mechanisms that appear in the works of her father, Sigmund Freud: repression, regression, reaction formation, isolation, undoing, projection, introjection, turning against one's own person, reversal into the opposite, and sublimation or displacement.
Examples of associative mechanisms are commonly found in the chemistry of 16e square planar metal complexes, e.g. Vaska's complex and tetrachloroplatinate. The rate law is governed by the Eigen–Wilkins Mechanism. Dissociative substitution resembles the S N 1 mechanism in organic chemistry.
The bimolecular nucleophilic substitution (S N 2) is a type of reaction mechanism that is common in organic chemistry. In the S N 2 reaction, a strong nucleophile forms a new bond to an sp 3 -hybridised carbon atom via a backside attack, all while the leaving group detaches from the reaction center in a concerted (i.e. simultaneous) fashion.
The Eigen-Wilkins mechanism, named after chemists Manfred Eigen and R. G. Wilkins, [5] is a mechanism and rate law in coordination chemistry governing associative substitution reactions of octahedral complexes. It was discovered for substitution by ammonia of a chromium-(III) hexaaqua complex.
Examples of anomalous diffusion in nature have been observed in ultra-cold atoms, [3] harmonic spring-mass systems, [4] scalar mixing in the interstellar medium, [5] telomeres in the nucleus of cells, [6] ion channels in the plasma membrane, [7] colloidal particle in the cytoplasm, [8] [9] [10] moisture transport in cement-based materials, [11 ...
The Kirkendall effect is the motion of the interface between two metals that occurs due to the difference in diffusion rates of the metal atoms. The effect can be observed, for example, by placing insoluble markers at the interface between a pure metal and an alloy containing that metal, and heating to a temperature where atomic diffusion is reasonable for the given timescale; the boundary ...
A typical representative organic reaction displaying this mechanism is the chlorination of alcohols with thionyl chloride, or the decomposition of alkyl chloroformates, the main feature is retention of stereochemical configuration. Some examples for this reaction were reported by Edward S. Lewis and Charles E. Boozer in 1952. [2]