Chemical properties of substances


Chemical energy is a type of stored energy present in the atoms which can hold the molecule together. It is a form of energy in the bonds of chemical compounds. It occurs during a chemical reaction to produce in the form of heat or any mechanical work. The released energy transformed the substance into a new substance. For example, when oxygen combines with hydrogen, thermal and light energy released by the combustion, new covalent bonds are formed between oxygen and hydrogen atoms to form water. This change is permanent and irreversible as new products are formed.

There are two types of chemical energy: endothermic reaction (heat absorbed) and exothermic reaction (heat released) during a chemical reaction. In an endothermic reaction, the heat is absorbed, creating cooling. In an exothermic reaction, heat is released, creating warmth and produced as a by-product. Therefore, chemical energy is measured and observed only when a chemical reaction occurs.

What is Energy?

It is the ability to do work. In other words, it is a force exerted to cause the displacement of an object. It is neither destroyed nor created but converted from one form to another. There are different forms of energy: kinetic energy, chemical energy, sound energy, electrical energy, gravitational energy, mechanical energy, heat energy, light energy, and potential energy.

Examples of Energy

  • Chemical energy is stored in substances like food and coal.

  • Nuclear energy is energy that releases in nuclear fusion during chemical reactions.

  • Electrical energy is energy in the form of kinetic or potential energy resulting from the flow of an electric charge.

  • Mechanical energy is the total energy in the form of potential and kinetic energy, such as peddling a moving bike.

  • Thermal energy is the heat produced during energy changes in the processes.

  • Radiant energy is the electromagnetic energy produced when waves travel through space.

What is Chemical Energy?

Chemical energy is the energy released during chemical reactions. It is the energy possessed or stored in the bonds of chemical compounds. It is either released in the making or breaking of the bonds in the form of heat. Burning wood and petrol in a car's engine is a chemical energy converted into thermal energy. Other examples are natural gas, batteries, coal, petroleum, and biomass.

The majority of chemical changes or chemical reactions proceed through combustion processes, which one has to properly control and monitor. The advantage of such a form of energy is its easy storage. For example, charging a battery is a form of chemical energy.

Chemical Energy in Everyday Life

The following are some examples of chemical energy or changes in daily life.

ComponentsChemical Change
BatteriesChemical energy is stored in the batteries and converted into electricity. During this process, the flow of electrons from one electrode to another provides a circuit to do work.
WoodThe chemical change occurs when the wood is burned, which in turn produces water, carbon dioxide, and ash.
FirecrackerThe explosion of firecrackers is a chemical change as the explosive material transforms into gaseous products along with light, heat, and sound. Therefore, burning crackers is a chemical change.
CarsA chemical change occurs while running a car when fuel burns in the form of combustion. When fuel burns, it releases energy to run a vehicle as oxygen combined with air and yields carbon dioxide and water, which are discharged into the air through the exhaust system.
FoodCooked food under go chemical change as raw ingredients are converted to delicious food, and cooked food cannot be converted to its original ingredients.
Petroleum and Natural GasBurning natural gas and petroleum combustion is a chemical change as it produces carbon dioxide and water.
CoalBurning coal is a chemical change that changes carbon to carbon dioxide.

Table-1: Components which contains chemical energy

Chemical Energy Examples

Chemical energy or change is a form of energy release When a chemical reaction undergoes the chemical changes and is transformed into other or new substances. The following are some examples −

  • Burn fossil fuels like natural gas, methane, petroleum, and oil to produce steam to turn turbines to produce electricity.

  • Combustible liquid fuels (engine oil, kerosene, diesel fuel) are chemical substances. They are a mixture of incandescent gases.On heating typically burns with lumino sity with intense heat.

  • Photosynthesis is the process of producing food by plants. In this process, light energy from the sun is converted into chemical energy. The chemical reaction that occurs in photosynthesis involves combining carbon dioxide and water to form oxygen and glucose.

  • Respiration in human beings causes oxygen intake in bodies, which combines with glucose. Glucose is produced by the breakdown of carbohydrates present in food. This glucose combines with oxygen in the cells of our body and provides energy. Hence, respiration causes chemical changes in the body.


Chemical energy is a form of stored energy in the bonds of chemical compounds. The release of energy during a chemical reaction in the form of heat or work is a chemical change . Therefore, forming new bonds and breaking old bonds results in energy change chemically. Though chemical energy has various advantages, there are some of its disadvantages. As chemical energy forms are a result of combustion, most by-products are not a clean form of energy, and emissions of such by-products would impact the planet negatively. In addition, chemical energy is also considered a non-renewable source of energy.


Q1. What creates chemical energy?

Ans. The energy stored in the bonds of chemical compounds at a molecular level is called chemical energy. During a chemical reaction, a new substance is formed on making and breaking of chemical compounds and thus releases energy, and the release of energy is chemical energy.

Q2. Is chemical energy kinetic or potential?

Ans. The energy stored in the chemical bonds is the stored energy that is released during the making and breaking of bonds, therefore, it is a form of potential energy.

Q3. Is fire chemical energy?

Ans. Fire results from the process of combustion (a chemical reaction). It is a process when fuel burns in the presence of oxygen. The products that form from the combustion reaction are completely different from the starting material. Therefore, fire is chemical energy.

Q4. What is chemical energy used by cells called?

Ans. The chemical energy used by cells is called adenosine triphosphate (ATP). It is a molecule that provides energy to the cells to perform work, such as moving muscles during a walk down the street.

Q5. How do we control chemical energy?

Ans. Chemical energy can be controlled by mechanical energy-isolating devices that can physically control the release or transmission of the chemical. These devices are to be handled carefully with chemicals.

Q6. Does the phone use chemical energy?

Ans. Yes, a phone uses chemical energy. Batteries on the phone contain chemical energy that transfers electrical energy (obtained due to charging) into powering it and also transfers energy into sound energy, light energy, and heat energy.

Q7. Why is sun tanning a chemical process?

Ans. A chemical change is any change that results in the formation of new chemical substances. During sun tanning, both melanin and vitamin D are produced. Hence, it is a chemical change.

Updated on: 18-Apr-2023


Kickstart Your Career

Get certified by completing the course

Get Started