11 Best Examples Of Chemical Change In Everyday Life

A chemical change is a process in which one or more substances are converted into one or more new and different substances. These substances can be either chemical elements or compounds.

Chemical changes occur as the result of chemical reactions. During a chemical reaction, atoms are rearranged, and the reaction is accompanied by an energy change as new substances are produced.

In other words, chemical changes are fundamental changes that generate new combinations of matter. These changes are usually irreversible or only reversible with an additional chemical change.

While hundreds of thousands of different chemical reactions exist, most of them have similar properties. These similarities enable us to classify chemical changes into three broad categories.

  • Organic changes involve chemical reactions of complex carbon compounds in which one or more carbon atoms are covalently linked to atoms of other elements, most commonly hydrogen, nitrogen, or oxygen.
  • Inorganic changes are chemical reactions of substances that, in general, do not involve carbon atoms. These changes typically occur in laboratories and heavy industries.
  • Biochemical changes occur in living organisms. They are controlled or moderated by hormones and enzymes.

To explain this process in more detail, we have listed a few most common examples of chemical change that you see in everyday life.

11. Baking a Cake

Type: Inorganic change

When you bake a cake, its ingredients (flour, egg, sugar, baking powder, etc.) go through a chemical change. This is what happens during the baking process:

  • Heat allows baking power to form tiny bubbles of gas, which makes the cake fluffy
  • Heat causes egg protein to change and make the cake firm
  • The oil keeps the heat from drying out the cake

Since this baking process requires heat, it’s an endothermic reaction. It cannot be reversed as the sugar and the yeast have created new substances. This means once you bake a cake, you cannot separate it into its original components (flour, eggs, sugar).

10. Burning Of A Natural Gas

Type: Organic change

Natural gas is a hydrocarbon mixture of many different compounds. Its main constituent is methane (CH4), a compound with one carbon atom and four hydrogen atoms. When methane is burnt in the presence of air (oxygen), it produces water, carbon dioxide, and heat (in the form of blue flame). 

This combustion reaction is the basis for a significant fraction of the world’s energy. It is used for heating water, cooking food, electricity generation, and other essential purposes.

9. Explosion Of Fireworks

Type: Inorganic change

Fireworks are a great combination of science and innovation. They are made of high-energy compounds, which create explosions. When you provide enough heat (activation energy), they undergo several chemical reactions in rapid sequence.

More specifically, the high-energy compounds densely packed inside the firework burn with oxygen in the air and convert themselves into other compounds, releasing sound, heat, and gases (like carbon monoxide, carbon dioxide, and nitrogen) in the process.

Different compounds give off different colors and shades that we see in the dark night sky. Barium, for example, produces green color, copper creates a blue color, sodium generates a yellowish-orange color, and strontium gives rise to a red color.

8. Ripening of Fruits

Ripening of Ziziphus jujuba

Type: Organic change

Ripening is associated with changes in compositions (like conversion of starch to sugar). It’s a process by which fruits attain their desirable flavor, color, quality, and other characteristics. On the basis of ripening nature, fruits can be classified into two groups:

  • Climacteric fruits can ripen after being removed from the plant. For example, banana, mango, and apple continue to ripen and cannot withstand rigors of transport and repeated handling.
  • Non-climacteric fruits cannot ripen once harvested. They produce small amounts of ethylene (far less than climacteric fruits) and do not respond to ethylene treatment. Examples include orange, grapes, blackberry, pomegranate, and watermelon.

Since ripening includes the formation of new carbon-containing chemicals that result in a change of color and taste, one can safely term the ripening process as organic chemical change.

7. Food Digestion

Type: Organic

Unlike mechanical digestion, which starts in your mouth with chewing, chemical digestion is a complex process that breakdowns food into its building blocks. These building blocks are eventually absorbed into the blood plasma to nourish the body cells.

More specifically, large food molecules are reduced to subunits that are small enough to be absorbed by the lining of the alimentary canal.

  • Proteins break down into amino acids
  • Nucleic acids break down into nucleotides
  • Carbohydrate sugars break down into monosaccharides
  • Fats break down into fatty acids and monoglycerides

This is achieved by various enzymes (such as salivary, gastric, brush border, and pancreatic enzymes) through hydrolysis.

6. Electroplating A Metal

Type: Inorganic change

Electroplating is the process of depositing material on a solid substrate using an electric current. It is used to enhance the chemical, physical, and mechanical properties of the substrate.

In this process, a solution containing metal ions is placed in a tank, and the substrate to be plated is attached to the electrical supply to make it a cathode. The metal ions in the solution move toward the cathode, where they gain electrons and form a metal coating.

A common form of electroplating is used to produce coins. The US penny, for example, is made of zinc covered in a layer of electroplated copper.

5. Souring Of Milk

Type: Organic change

Spoiled milk is sour, with a foul odor and taste. It becomes lumpy and curdled over time. The souring process produces new molecules, and it is not something you can reverse.

Raw milk contains the sugar lactose. When left at room temperature for several hours, the lactobacillus bacteria in milk start converting lactose into lactic acid, which has a sour taste. Lactobacillus bacteria are commonly found in milk, and they do cause any harm.

Soured milk is also produced by adding acid (with or without the addition of microbial organisms). This is called acidified milk. It tastes different than the milk produced by bacterial fermentation because the acids added in the commercial manufacturing process have different flavors than lactic acid.

4. Mixing An Acid With A Base

Type: Inorganic change

Mixing an acid with a base is one of the most common chemical reactions performed in chemistry labs. When mixed in equal proportion, they cancel each other out and produce salt and water. It is called a neutralization reaction.

For example, a reaction between hydrochloric acid (strong acid) and sodium hydroxide (strong base) produces sodium chloride (table salt).

HCl + NaOH → NaCl + H2O + heat

What happens in such reactions is H(+) cation of acid combines with the OH(-) anion of the base to form salt and water.

Some reactions produce gases. For instance, when you mix vinegar (a weak acid) with baking soda (a weak base), you get carbon dioxide (gas) along with sodium acetate (salt).

Read: 8 Strongest Acids Ever Known To Us

3. Rusting Iron

Type: Inorganic change

When iron objects are left in water or moist atmosphere for a considerable time, they get covered with a reddish-brown flaky matter called rust. Rusting is a continuous process that gradually degrades objects and makes them useless. Various factors, such as acid environment and saltwater, can speed up the rusting of iron.

Rust is nothing but Iron Oxide, a compound formed when iron reacts with oxygen and water. Although it’s a complex process, its chemical equation can be written as:

4Fe + 3O2 + 6H2O → 4Fe(OH)

This process is also a good example of corrosion, where metal surfaces are degraded into more chemically stable oxides.

2. Boiling An Egg

Type: Inorganic change

Raw eggs contain complex networks of protein and water. There are nearly one thousand water molecules to every one protein molecule.

Protein molecules are relatively big, containing hundreds of amino acids bound together into long chains. The chains are folded into compact globs, and these globs are held together by weak chemical bonds (non-covalent).

When you apply heat to eggs, their molecules move faster and collide.  As the temperature rises, the rate of collision increases. The weak bonds (that hold the amino acid chains) start breaking apart, and the egg proteins unfold. Eventually, the protein strings become tangled into a three-dimensional web.

The boiled egg now contains water that is dispersed in the protein web so it can no longer flow together. And this turns the liquid egg into a semi-solid.

Basically, you have changed the chemicals that make up the egg by applying heat. It’s an irreversible change, which means the cooked egg cannot be turned back into a raw egg.

1. Photosynthesis

Type: Biochemical change

Photosynthesis is a process used by plants and other organisms to produce their food. In this natural process, light energy (sunlight) is converted into chemical energy.

Plants are primary producers that form the base of our ecosystem and fuel the next trophic levels. They use photosynthesis to transform sunlight, water, carbon dioxide into oxygen and simple sugar.

6CO2 + 6H2O + Light energy → C6H12O6 (sugar) + 6O

Since photosynthesis requires external energy (sunlight) to drive the chemical change, it is an endothermic reaction. This process is not only used by plants to make food and grow, but it also has a massive effect on our atmosphere and oceans because it absorbs carbon dioxide and produces oxygen.

Without photosynthesis, there would be too little oxygen on Earth — it won’t be enough for humans to survive.

Read: 12 Examples Of Thermal Energy In Everyday Life

Frequently Asked Questions

What is the difference between chemical change and physical change?

A physical change affects the form of a substance. It involves changes in properties such as strength, durability, melting point, crystal form, volume, density, shape, size, color, and texture. A good example would be tempering steel to form a knife blade.

The chemical change, on the other hand, involves alterations in the composition of the substance. It occurs when different substances combine to form new substances with new properties. These chemical reactions are irreversible and accompanied by an energy change.

How to Identify a chemical change?

It is not always easy to figure out whether a chemical change has occurred (as opposed to a physical change). However, one can look for signs such as:

  • Change of color or order
  • Decomposition of organic matter like food and vegetables
  • Change in energy or temperature, such as loss (endothermic) or production (exothermic) of heat
  • Formation of gases or precipitate
  • Change in composition, such as woods become ash when burned
  • Changes impossible to reverse
  • Some chemical reactions produce light

Read: 14 Best Examples Of Radiation And Their Effects

Which substance cannot be altered by ordinary chemical changes?

An element is a pure substance that can never be reduced to a simpler form by any chemical reaction. This means you cannot convert an element into another element or decompose it via ordinary chemical means such as electrolysis, heating, or reaction. Oxygen, nitrogen, gold, and silver are examples of pure substances.

Written by
Varun Kumar

Varun Kumar is a professional science and technology journalist and a big fan of AI, machines, and space exploration. He received a Master's degree in computer science from GGSIPU University. To find out about his latest projects, feel free to directly email him at [email protected] 

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