Written By Adeel Abbas
A fundamental aspect of our world is that chemical changes take place. They transform one substance into another.
All these changes can be observed in a variety of natural and human-made processes, from the rusting of iron to the burning of fossil fuels.
The list of chemical changes in this chapter tells about diverse range of reactions that occur in our everyday lives and shows the important role that chemistry plays in understanding and shaping our world.
Also read: Difference between chemical and physical change
20 Examples of chemical change
Here are 20 examples of chemical changes.
1. Rusting of iron
iron is an example of chemical change in daily life. When iron is exposed to oxygen and moisture over time, it undergoes a chemical reaction known as rusting. This results in a reddish-brown layer of iron oxide on the surface of the metal.
2. Burning of wood
it is the most common example of chemical change in daily life. When we burn wood, it undergoes a chemical reaction with oxygen in the air. This process releases energy in the form of heat and light. The chemical reaction converts the complex organic molecules in wood into simpler molecules such as carbon dioxide, water vapor, and ash.
3. Digestion of food
Another important example of chemical change is the process of digestion. It involves a series of chemical reactions that break down food into simpler molecules that can be absorbed by the body. Enzymes in the digestive system catalyze these reactions, breaking down carbohydrates, proteins, and fats into glucose, amino acids, and fatty acids.
4. Fermentation of alcohol
Fermentation is a process in which sugars are converted into alcohol and carbon dioxide by microorganisms such as yeast. This is a chemical reaction that is used in the production of alcoholic beverages such as beer and wine.
5. Cooking an egg
When an egg is cooked, the heat causes the proteins in the egg to denature and coagulate, resulting in a solid and opaque structure. This chemical change alters the texture and taste of the egg.
6. Bleaching of hair
When hair is bleached, a chemical reaction occurs between the bleach and the melanin pigment in the hair. This breaks down the pigment and lightens the hair color.
7. Tarnishing of silver
When silver is exposed to air and sulfur compounds, a chemical reaction occurs that results in a darkening of the metal known as tarnishing.
8. Formation of rust on copper
When copper is exposed to acidic or humid conditions, it can undergo a chemical reaction that results in the formation of greenish-brown copper carbonate or copper sulfate.
9. Ripening of fruit
The ripening of fruit involves a series of chemical reactions that break down complex organic molecules such as starch and acids into simpler molecules such as sugars, which give the fruit a sweeter taste.
10. Combustion of gasoline
When gasoline burns in an engine, it starts a chemical reaction with oxygen in the air, producing energy in the form of heat and motion. The combustion of gasoline produces carbon dioxide and water vapor as byproducts.
11. Decay of organic matter
The decay of organic matter such as food waste or leaves involves a complex series of chemical reactions that break down the organic molecules into simpler molecules such as water, carbon dioxide, and methane.
12. Electroplating of metals
Electroplating is a process in which a metal is coated with a thin layer of another metal through an electrochemical reaction. This changes the properties of the metal, such as its conductivity or resistance to corrosion.
13. Formation of a patina on bronze
When bronze is exposed to air and moisture over time, it can undergo a chemical reaction that results in the formation of a greenish-brown layer known as a patina. This is a protective layer that can prevent further corrosion of the metal.
14. Polymerization of plastics
The process of polymerization involves a chemical reaction that links together small molecules known as monomers to form larger molecules known as polymers. This is used in the production of plastics, which are composed of long chains of polymers.
15. Curing of concrete
The process of curing concrete involves a chemical reaction between the cement and water, resulting in the hardening of the concrete over time
16. Photosynthesis in plants
Photosynthesis is a complex chemical process that occurs in plants, in which carbon dioxide and water are converted into glucose and oxygen in the presence of sunlight. This chemical change is essential for the survival of plants and the production of oxygen in the atmosphere.
17. Burning of fossil fuels
When fossil fuels such as coal or oil are burned, they undergo a chemical reaction that releases energy in the form of heat and light. This process also releases carbon dioxide and other pollutants into the atmosphere, contributing to global climate change.
18. Corrosion of batteries
When batteries are left unused for a long period of time, they can undergo a chemical reaction that results in the corrosion of the battery terminals. This can affect the performance of the battery and even render it unusable.
19. Decomposition of hydrogen peroxide
Hydrogen peroxide is a chemical compound that can decompose into water and oxygen over time or when exposed to heat or light. This chemical reaction is used in the production of rocket fuel and in the bleaching of hair.
20. Etching of glass
Etching is a process in which glass is treated with an acidic or caustic substance, resulting in a chemical reaction that removes a layer of the glass surface. This creates a design or pattern on the glass, and is commonly used in the production of decorative glassware.