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Where does the energy come from in an exothermic and endothermic reaction?
Wiki User
∙ 11y ago
The difference really lies in the stability of bonding, but it still doesn't answer how the energy is released, in what form. My Chem teacher mentioned a long time ago hinting while discussing E=mc2 that the energy released from chemical exothermic reactions is the conversion of mass to energy, and that in order to attain endothermic reactions one has to effectively 'add mass' to complete it in the form of energy.
Even this doesn't answer the question though, because saying energy just gets released into an extremely disordered state of energy such as heat doesn't work for me. Since heat is really just a descriptive word for describing the event of an increases and decrease in temperature which in turn is really just a distribution of particle velocities in a given space.
Suppose a unstable high energy tri-bond is broken and the chemical A1 reacts which A2 to make products B1.
Energy is first attained (Activation energy), pushed over an intermediate point where all chemical potential energy can be considered free-energy, where particles are completely indecisive about what they want to be. Then a chain reaction occurs whereby most of the free-energy is absorbed in the form of a more stable bond leaving behind residual energy. What this "free energy" manifests itself as is a mystery to me, but in consideration that pretty much every 'small' event is quantised it wouldn't surprise me if there was a massive amount of physics going on to transfer chemical energy potential differences into raw energy.
You have to understand there are also like a hierarchy of energy disorder. From most ordered being electrical, and magnetic, then to light, then heat, something like that, but there are complex process' of decay into the lower states and different chemical/physical theories which account for each drop.
There is a lot of reading and physical mechanism to wrap your head around to really answer the question.
Wiki User
∙ 9y ago
Wiki User
∙ 13y agofrom it's excess chemical bonding or interaction energy to form product.
From A --> B
If energy contain in state A is higher than state B the process release heat for example changing of Liquid -> Solid or Gas -> Liquid or any common combustion process
If energy contain in state B is higher than state A the process absorb heat for example changing of Solid -> Liquid or Liquid -> Gas or dissolving of salt into water.
Wiki User
∙ 13y agoChemical bonding required energy to break and reform the bond to different state or compound.
Different chemical bond such as bond between Carbon - Hydrogen had different strength and require different energy amount compare to bond Carbon - Oxygen.
When reaction form new compound, if the new compound or product bond strength is lesser than the original compound then the excess energy is release and the reaction is exothermic. If the new compound had higher bond strength the energy is absorb from environment and reaction is endothermic.
For process of freezing/condensing or dissolve of salt/sugar into water. The process involve various interaction force and if the net energy in previous state is more than the net energy after such interaction then the process is also exothermic.
Wiki User
∙ 12y agoThe energy comes from differences in bond enthalpy, which is, in short, the energy stored inside the bonds. An exothermic reaction is a reaction in which the bonds of the products are stronger, shorter, more stable, and lower in energy than the products. It takes energy to break bonds, but energy is released upon formation of bonds. If more energy is released from the formation of bonds than energy is used for the breaking of bonds, then the reaction is exothermic. Therefore, you could say that the energy comes from formation of bonds.
Wiki User
∙ 11y agoExothermic reactions release energy ... this is energy from the bonds in the compounds. Ex. oxygen - oxygen bonds contain a lot of energy. Carbon - hydrogen bonds in gasoline also has a lot of energy. When (during burning) these bonds are broken and new bonds, hydrogen - oxygen to form water vapor, and carbon - oxygen bonds to form carbon dioxide, the new bonds have less energy and the extra energy is released as heat and light.
Endothermic reactions are the opposite. The new bonds require more energy. This comes from heating the substances, or sometimes, comes from the surrounding environment. Absorbing heat energy from the environment makes everything decrease in temperature so the reaction 'feels' cooler.
Wiki User
∙ 7y agoThe energy is from an external source.
Wiki User
∙ 12y agoIt comes from the reactants and products.
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How do endothermic and exothermic differ?
Exothermic reactions release energy (usually as heat) into the surrounding environment - endothermic reactions absorb energy from the surrounding environment. Note that exothermic reactions are capable of turning into runaway reactions as the heat of reaction often speeds up the rate of reaction (releasing more heat, etc). Endothermic reactions are, usually, self moderating as a limited amount of energy is capable of being drawn from the surrounding environment.
What the distinguish between exothermic and endothermic?
Endothermic reactions are reactions that create bonds between atoms, which means they require energy, so they take heat energy from its surroundings to create the bonds (meaning the reaction produces "cold"), and exothermic reactions are ones which break bonds between atoms, giving off energy and thus heat.
Where does energy come from an endothermic reaction?
From the surroundings. From Wikipedia: "...a process or reaction in which the system absorbs energy from its surroundings in the form of (usually, but not always) heat."
When a match is struck and a flame is ignited where does the energy from the fire come from and where does it go?
Burning is an exothermic chemical reaction; heat is released in the atmosphere.
Is neutralization an endothermic or exothermic process?
neutralization is exothermic because the reaction of the strang base and strong acid produces heat. In other words, if you take the enthalpy of the products minus that of the reactants, you will find that the overall enthalpy is negative. Hope that helps!
How do endothermic and exothermic differ?
Exothermic reactions release energy (usually as heat) into the surrounding environment - endothermic reactions absorb energy from the surrounding environment. Note that exothermic reactions are capable of turning into runaway reactions as the heat of reaction often speeds up the rate of reaction (releasing more heat, etc). Endothermic reactions are, usually, self moderating as a limited amount of energy is capable of being drawn from the surrounding environment.
Where does the energy come from when a fuel is burnt?
Hydrocarbon exothermic reaction with O2
What is the reaction involved in dissolving sodium carbonate in water an endothermic reaction or exothermic reaction?
Dissolving Sodium Carbonate is an exothermic reaction. Exothermic reactions give out heat. When atoms, molecules or ions come together energy is released. The water molecules bond with the sodium carbonate molecules and more energy is released during this reaction than required to create the bonds. More energy means the molecules of the solution move faster and the temperature of the solution increases, thus increasing the temperature of the surroundings. Hope that helps :)
What the distinguish between exothermic and endothermic?
Endothermic reactions are reactions that create bonds between atoms, which means they require energy, so they take heat energy from its surroundings to create the bonds (meaning the reaction produces "cold"), and exothermic reactions are ones which break bonds between atoms, giving off energy and thus heat.
Where does energy come from an endothermic reaction?
From the surroundings. From Wikipedia: "...a process or reaction in which the system absorbs energy from its surroundings in the form of (usually, but not always) heat."
Where does the energy come from that is needed for an endothermic reaction the products or the reactants?
-The Productt/reactant solution -The envoriment when no solution is involved
When a match is struck and a flame is ignited where does the energy from the fire come from and where does it go?
Burning is an exothermic chemical reaction; heat is released in the atmosphere.
Why you need a body temperature?
The human body relies on chemical reactions to turn the food you consume into energy. The food you consume also goes into the production of cells inside your body. These processed require chemical reactions. There are two chemical reactions, endothermic and exothermic. Endothermic reactions require energy. Your "body temperature" fuels these reaction as heat is a form of energy. Exothermic reactions give off energy. Your body temperature is created from this type of reaction. As your core temperature lowers, as in hypothermia, the chemical processes in your body slow down, due to the lack of energy. Eventually it reaches a point to where the processed come to a stop. At that point, your brain is no longer able to send electrical impulses to your heart.
Where does the energy to cook food come from when a gas stove burns natural gas CH4 and oxygen O2?
The reaction CH4 + 2O2 ----> CO2 + 2H2O releases heat, it is an exothermic reaction.
Why is it necessary to burn the natural gas in the primary reformer Haber process?
the Haber process is endothermic. Energy to make the reaction take place must come from something.
Is neutralization an endothermic or exothermic process?
neutralization is exothermic because the reaction of the strang base and strong acid produces heat. In other words, if you take the enthalpy of the products minus that of the reactants, you will find that the overall enthalpy is negative. Hope that helps!
Is fermentation an exothermic or endothermic process?
It is exothermic reaction. Why should bacteria go and spend energy to ferment any thing should a question, come to your mind. I view the situation in terms of the energy levels. In a typical glucose fermentation, you start with high energy glucose. The final product after, for example human digestion is considered, is low energy carbon dioxide and water. Some way down the slippery slope you have alcohol, i.e. energy has been lost = exotherm. To give an example, a typical beer fermentation can increase in temperature at the rate of 0.6'C per hour, but this depends on the fermentation temperature, the yeast and the amount of glucose present. Without cooling, the temperature of the fermentation increases such that the character of the final prodcut is adversely affected.
