A chain reaction is a sequence of reactions where a reactive product or by-product causes additional reactions to take place. In a chain reaction, positive feedback leads to a self-amplifying chain of events.
Chain reactions are one way in which systems which are in thermodynamic non-equilibrium can release energy or increase entropy in order to reach a state of higher entropy. For example, a system may not be able to reach a lower energy state by releasing energy into the environment, because it is hindered in some way from taking the path that will result in the energy release. If a reaction results in a small energy release making way for more energy releases in an expanding chain, then the system will typically collapse explosively until much or all of the stored energy has been released. Since chain reactions result in energy transformation into forms associated with larger amounts of entropy. In accordance with the laws of thermodynamics, these reactions cannot be reversed.
A macrosopic metaphor for chain reactions is thus a snowball causing larger snowfall until finally an avalanche results ("snowball effect"). This is a result of stored gravitational potential energy seeking a path of release over friction. Chemically, the equivalent to a snow avalanche is a spark causing a forest fire. In nuclear physics, a single stray neutron can result in an prompt critical event, which may be finally be energetic enough for a nuclear reactor meltdown or (in a bomb) a nuclear explosion.
Other articles related to "chain reaction, reaction, chain, reactions":
... In a chemical reaction, every step of H2 + Cl2 chain reaction consumes one molecule of H2 or Cl2, one free radical H· or Cl· producing one HCl molecule ... Polymerase chain reaction, a technique used in molecular biology to amplify (make many copies of) a piece of DNA by in vitro enzymatic replication using a DNA ...
... Lariat Chain was developed from an earlier Tuck piece entitled Chain Reaction (1984) ... Chain Reaction was hand cranked, and utilized a heavy chain attached by magnets onto an iron flywheel ... As in Lariat Chain, Chain Reaction used a brush to affect the motion of the traveling chain ...
... physics, nuclear fission, and heavy water The key to maintaining a nuclear reaction within a nuclear reactor is to use the neutrons being released during fission to stimulate fission in other nuclei ... With careful control over the geometry and reaction rates, this can lead to a self-sustaining chain reaction, a state known as "criticality". 235U, on the other hand, can support a self-sustained chain reaction, but due to the low natural abundance of 235U, natural uranium cannot achieve criticality by itself ...
... Chain Reaction was a German record label founded in 1995 by Basic Channel members Moritz Von Oswald and Mark Ernestus ... and minimalism, but some have found Chain Reaction's output to be more "avant experimental." Notable atists releasing their records on label include Monolake, Porter Ricks, Vainqueur and Fluxion ...
... Antioxidants are used to terminate the oxidation reactions taking place due to different weathering conditions and reduce the degradation of organic ... Organic materials undergo auto-oxidizations due to free radical chain reaction ... Then this reaction comes to, 2R• → R—R ROO• + R• → ROOR 2ROO• → Non-radical products Weathering of polymers is caused by absorption of ...
Famous quotes containing the words reaction and/or chain:
“Sole and self-commanded works,
Fears not undermining days,
Grows by decays,
And, by the famous might that lurks
In reaction and recoil,
Makes flames to freeze, and ice to boil.”
—Ralph Waldo Emerson (18031882)
“The conclusion suggested by these arguments might be called the paradox of theorizing. It asserts that if the terms and the general principles of a scientific theory serve their purpose, i. e., if they establish the definite connections among observable phenomena, then they can be dispensed with since any chain of laws and interpretive statements establishing such a connection should then be replaceable by a law which directly links observational antecedents to observational consequents.”
—C.G. (Carl Gustav)