A reaction occurs spontaneously when free energy is negative, ie the disorder of the system is increasing
You would expect a catabolic reaction to be spontaneous because this type of reaction involves the release of energy. You would expect reactions that require energy (anabolic reactions) not to be spontaneous due to the need for an input of energy.
Exothermic, as endothermic reactions require activation energy.
For some non-spontaneous reactions, you can change the temperature. For other non-spontaneous reactions, there is nothing you can do to make it spontaneous. Nature favors reactions that increase a system's entropy (disorder) and nature favors reactions that are exothermic (they release enthalpy). Any reaction that does both of these things is spontaneous at all temperatures. Any reaction that does neither of these things is never spontaneous. As far as this question is concerned, the interesting reactions are endothermic reactions that increase entropy and exothermic reactions that decrease entropy. Whether these reactions are spontaneous depends on the temperature. The first variety (endothermic, increase entropy) will be spontaneous at high temperatures; the second (exothermic, decrease entropy) will be spontaneous at low temperatures. To find the temperature at which a reaction becomes spontaneous, one may apply the Gibbs equation: DG = DH - TDS where capital Ds stand for the Greek capital delta.
The reaction happens by itself.
The chemical reactions of metabolism are organized into metabolic pathways, in which one chemical is transformed through a series of steps into another chemical, by a sequence of enzymes. Enzymes are crucial to metabolism because they allow organisms to drive desirable reactions that require energy and will not occur by themselves, by coupling them to spontaneous reactions that release energy.
it doesn't its energy releasing reaction
You would expect a catabolic reaction to be spontaneous because this type of reaction involves the release of energy. You would expect reactions that require energy (anabolic reactions) not to be spontaneous due to the need for an input of energy.
An exothermic reaction (often a spontaneous one)
Exothermic, as endothermic reactions require activation energy.
This is a very fast reaction.
For some non-spontaneous reactions, you can change the temperature. For other non-spontaneous reactions, there is nothing you can do to make it spontaneous. Nature favors reactions that increase a system's entropy (disorder) and nature favors reactions that are exothermic (they release enthalpy). Any reaction that does both of these things is spontaneous at all temperatures. Any reaction that does neither of these things is never spontaneous. As far as this question is concerned, the interesting reactions are endothermic reactions that increase entropy and exothermic reactions that decrease entropy. Whether these reactions are spontaneous depends on the temperature. The first variety (endothermic, increase entropy) will be spontaneous at high temperatures; the second (exothermic, decrease entropy) will be spontaneous at low temperatures. To find the temperature at which a reaction becomes spontaneous, one may apply the Gibbs equation: DG = DH - TDS where capital Ds stand for the Greek capital delta.
non spontaneous process happen in the universe but energy has to be provided to them . the free energy change of such processes are positive . the amount of temperature has to be increased to carry out such reactions
stimulated emission causes due to the energy difference between the higher and lower energy level state, but it doesn't depends in the case of spontaneous emission . spontaneous emission causes without any stimulation .In stimulated emission energy transfer is twice the energy transfer of spontaneous emission.
stimulated emission causes due to the energy difference between the higher and lower energy level state, but it doesn't depends in the case of spontaneous emission . spontaneous emission causes without any stimulation .In stimulated emission energy transfer is twice the energy transfer of spontaneous emission.
Endergonic means "absorbing energy in the form of work." Endergonic reactions are not spontaneous. An exergonic reaction is a chemical reaction where the change in the free energy is negative, indicating a spontaneous reaction.
Describe the connection between the sun's energy and the wind.
The difference can be clarified by entropy (the second rule of thermodynamics).The reaction is more spontaneous with higher entropy, for the reactions that occur spontaneously the entropy is higher than for the ones that do not.