Chemical energy with important examples.

You might have heard about chemical energy. But what is the definition of chemical energy? When and where chemical energy is stored or released? Chemical energy is the energy stored in chemical substances and is released when they go through chemical reactions.

Chemical energy:

Chemical energy is the energy stored in chemical substances and is released when they go through chemical reactions. In fact, such energy is stored in the chemical bonds of the substances, the breaking, and remaking of chemical bonds cause a chemical reaction that often releases energy in the form of heat.

Some inputs like energy or heat and other agencies are needed for chemical reactions. For example for photosynthesis inputs or reactants such as carbon dioxide, and sunlight (heat) are required. During such types of transformations, some heat energy(sunlight) is converted to chemical energy.

It is also a form of potential energy possessed by atoms and molecules and is released during chemical reactions and can be converted or changed into other forms. During conversion, chemical energy is often released or absorbed energy in the form of heat.

The energy released or absorbed in the process is equal to the difference between the energy content of the final products and the reactants, provided the initial and final temperature is the same.

Further, a fuel cell converts the chemical energy of hydrogen or other fuels to clean electrical energy, heat, and water through a redox reaction.

Important examples of Chemical energy:

We encounter many examples of chemical energy in our day-to-day life.

• Coal is a sedimentary rock and is mostly composed of carbon and hydrocarbons containing chemical energy converted to heat and light by combustion reaction.
• Charcoal is mostly made up of carbon when burnt it undergoes a chemical reaction and produces heat and light.
• Wood is another substance that converts chemical energy into heat and light energy when put into combustion.
• Gunpowders are mostly composed of charcoal which undergoes chemical reactions to form heat and light energy etc.
• Petroleum in combustion reaction release light and heat or another form of chemical energy like gasoline.
• Natural gas is very familiar in commercial as well as domestic sectors. It is a mixture of hydrocarbons made up of mostly methane(CH₄) when burnt undergoes a chemical reaction and produces heat and light.
• Biogas is mostly composed of methane and carbon dioxide when undergoes a combustion reaction converts the chemical energy into heat and light energy.
• We take food to live is known to everybody. Our body mechanism converts the chemical energy of the food into mechanical energy and heat.
• Photosynthesis is another example involving chemical energy. During photosynthesis, the plant converts the (sunlight)solar energy into chemical energy mostly in the form of oxygen.
• A battery or cell converts stored chemical energy into electrical energy.
• The cold pack includes a cold / ice bag, a mixture of salts such as potassium chloride or soda, and water. The mixture undergoes a chemical reaction and chemical energy is absorbed in it.
• The hot pack undergoes exothermic chemical reactions to produce heat energy.
• A fuel cell converts chemical energy to electrical energy, heat, and water through electrochemical reactions.
• Propane is an alkane gas(C₃H₈) sometimes referred to as LPG(propane and butane) when undergoes a chemical reaction that produces heat, CO₂, and water.
• In the cellular respiration process, the organisms use oxygen to break down the food molecules to generate carbon oxide, water, and chemical energy in the form of ATP(Adenosine triphosphate) for cell function.

Conclusion:

Chemical energy is the stored energy of molecules and atoms. When undergoes chemical reaction under the influence of an external agency like fuel or energy, it often produces heat and other products. Plenty of examples of chemical energy are there as discussed above.