Difference between endothermic reactions and exothermic reactions
The main difference between endothermic reactions and exothermic reactions is that endothermic reaction is a type of reaction in which heat is absorbed from the environment, while exothermic reaction is the reaction in which heat is released into the environment …
Endothermic reactions versus exothermic reactions
On the basis of energy or heat, chemical reactions are classified into two main types, that is, endothermic reactions and exothermic reactions. Endothermic reactions are those reactions that absorb energy in the form of heat from the environment, while exothermic reactions release energy to the environment. Therefore, energy must be provided in case of an endothermic reaction, but the exothermic reaction does not require energy. In an endothermic reaction, the substrate has less energy than the product, while in exothermic reactions, the substrate has more energy compared to the product. This change in energy during different reactions is called the heat of reaction and is known as enthalpy. It is denoted by ‘ΔH’ and is expressed in kJ / mol.
Comparative chart
Endothermic reactions | Exothermic reactions |
A reaction in which the system absorbs energy from the environment is called an endothermic reaction. | A reaction in which the system releases energy into the environment is called an exothermic reaction. |
Sense | |
Endothermic is derived from the Greek word where “Endo” means “inside” while “Thermal” means “heat.” | Exothermic is derived from a Greek word where “Exo” means “outside” while “Thermal” means “heat.” |
Power requirement | |
Endothermic reactions require energy to complete. | Exothermic reactions do not require energy. |
Reagents and products | |
Endothermic reactions have low energy reactants but high energy products. | Exothermic reactions have high-energy reactants but low-energy products. |
Ambient | |
The endothermic reaction cools the environment by absorbing energy. | The exothermic reaction heats the environment by releasing temperature. |
Energy form | |
Energy is absorbed in an endothermic reaction. | In exothermic reactions, energy is generally released in the form of heat, but it can also be in the form of electricity, light, or sound. |
Enthalpy (ΔH) | |
ΔH is positive in an endothermic reaction because heat is absorbed. | ΔH is negative in an exothermic reaction, since heat is given off. |
Request | |
It has applications in thermodynamics; Chemistry physics. | It is also used in thermodynamics; Chemistry physics. |
Examples | |
Photosynthesis, reaction of ethanoic acid with sodium carbonate | Explosions, iron oxidation, coal burning, chemical bonding, nuclear fission, and fusion are examples of exothermic reactions. |
The word endothermic is derived from a Greek word where “Endo” means “inside” while “Thermal” refers to “heat”, so an endothermic reaction is the reaction in which heat is absorbed from the environment. Heat must be supplied in case of an endothermic reaction. Two or more molecules or reagents react in the presence of heat to produce the product. So it cools the surrounding environment by absorbing energy through it. In addition, it stores energy in the form of chemical bonds in the product. Therefore, in the case of an endothermic reaction, the product has more energy than the reactants. It has applications in thermodynamics; Chemistry physics. Furthermore, the value of ΔH is always positive due to the absorption of heat during the reaction.
Example
Photosynthesis is a type of endothermic reaction in which chlorophyll uses carbon dioxide plus water and energy from sunlight to produce glucose and oxygen.
What are exothermic reactions?
The word exothermic is derived from a Greek word in which “exo” means “outside” while “Thermal” refers to “heat.” So the exothermic reaction is the reaction in which heat is released into the environment. Heat is released in the case of exothermic reaction. Sometimes it is harmful if the reaction occurs at a higher rate. Two or more molecules react to form a product releasing energy. So as a result, the temperature of the surrounding environment increases. Therefore, in the case of an exothermic reaction, the reactants have more energy than the product. It also has applications in thermodynamics; Chemistry physics. During the exothermic reaction, the value of ΔH is always negative due to the release of energy.
His example is a campfire in which heat is released from the chemical bonds of paper and wood in the form of light and heat and warms the spectator present around him.
Key differences
- A type of reaction in which the system absorbs energy from the environment is called an endothermic reaction, while a type of reaction in which the system releases energy to the environment is called an exothermic reaction.
- In the word endothermic, “Endo” means “inside”, while “Thermal” means “heat” on the other hand, in the word exothermic, “exo” means “outside” while “Thermal” refers to “heat”.
- Endothermic reactions require energy to complete, while exothermic reactions do not require energy.
- Endothermic reactions have low energy reactants, but high energy products, conversely, exothermic reactions have high energy reactants but low energy products.
- The endothermic reaction cools the environment by absorbing energy from the other side; The exothermic reaction heats the environment by releasing temperature.
- Energy is absorbed in an endothermic reaction, whereas in exothermic reactions, energy is generally released in the form of heat, but it can also be in the form of electricity, light, or sound.
- During the endothermic reaction, the value of ΔH is always positive due to the absorption of heat, while in an exothermic reaction, the value of ΔH is always negative due to the release of energy.
- Photosynthesis is the example of endothermic reactions, while a campfire is the example of exothermic reactions.
Final Thought
From the above discussion, it is concluded that an endothermic reaction is a reaction that absorbs heat and stores it in the chemical bonds of its product, for example, photosynthesis, while the exothermic reaction is the reaction that releases the stored energy of its reactants. in the environment. eg campfire