How to Identify Chemical Changes: Signs, Types, and Examples
The description and justification of chemical changes is the main goal of the science of Chemistry. Many studies started with an experimental finding suggesting that understanding chemical change could not be as easy and obvious as it might seem. Even while many of the students in the Chemistry classes could define a chemical process and balance chemical equations, they exhibited a general lack of understanding of chemical changes, particularly those of chemical changes in daily life. Additional studies on education suggest that this trend of misunderstanding about chemical change among learners who have mastered equation-balancing abilities is likely a prevalent one. To avoid these types of issues, the better solution is to study the concept of chemical change by utilising examples of chemical changes.
What is the Concept of Chemical Change?
A chemical change is the conversion of one compound into another, where the old bonds are dissolved, and new bonds are created. New products are created via chemical changes. These mechanisms are referred to as chemical reactions, and they are typically irreversible excluding additional chemical reactions. Some reactions known as exothermic reactions produce heat, while others known as endothermic reactions might need heat to proceed. There are 3 different kinds of chemical changes: organic, inorganic, and biochemical.
Common chemical changes can be detected by the following signs:
Phase change
Composition change
Colour change
Odour change
Formation of precipitation
The breakdown of organic material
Formation of bubbles
Examples of Chemical Change and Physical Change
One can easily understand the changes in nature and process by certain examples of physical and chemical changes. Physical changes only cause a variation in appearance without altering the composition. Certain examples of physical changes are as follows:
Destroying a can
Melting of ice cubes
Heating water
Combining water and sand
Shattering glass
Dissolving water and sugar
Tearing up paper
Making woodcuts
Contrarily, chemical changes are very dissimilar. Whenever the material's constitution is altered, a chemical change takes place. A chemical reaction takes place when bonds are destroyed and fresh bonds are created. Examples of chemical changes include the development of the dye in the colour and the creation of a biochemical alteration in the hair through chemical reactions, and also chemical change triggers the oxidation reaction. Chemical changes occur everywhere, not only in research laboratories. The following section provides a few examples of chemical changes in our daily life.
Examples of Chemical Change in Our Daily Life
A natural atmosphere undergoes numerous changes. All of these modifications encompass a transformation in the state. Some examples of chemical change in our daily life include the following:
Digestion of food.
Spoiled eggs (Fermentation).
Cooking any dish.
Milk turning sour.
Several metabolic processes that occur within cells.
Violent reaction (fireworks).
Rusting of metals.
Gas formation.
Burning of woods or papers.
Acid-base reaction.
Formation of the black film when a glass held in a candle flame.
Examples of Colour Change in Chemical Reaction
The naked eye may not necessarily be able to see a chemical change, but occasionally, substance colours do change as a result of a chemical change. A distinct structure with a completely distinct composition and colour results from the reaction of two or more components. A chemical reaction can be seen by the colour shift.
Some of the examples of colour change in chemical reactions occur when:
One might notice that the metal has altered colour and become orange if one were to watch metal rusting throughout the period.
Chemical reactions involving pigments and hair molecules, and also peroxide and ammonium.
Blackening of sliced fruit and vegetable skins.
Bleaching clothes.
Conclusion
Therefore, during a chemical reaction, the substance's mass changes. The mass is either added or subtracted. The energy changes happen when a reaction takes place. Numerous chemical changes can be seen happening all around us. These chemical changes in daily life are necessary for human life and the survival of all other living things.
FAQs on Chemical Change Examples: Core Concepts & Real-Life Reactions
1. What is a chemical change in simple terms?
A chemical change is a process where one or more substances are transformed into entirely new substances with different properties. Unlike a physical change, the original substance is permanently altered. For example, burning wood turns it into ash and smoke, which are completely different from the wood itself.
2. What is the main difference between a physical and a chemical change?
The key difference is in the final product. A physical change, like melting ice into water, only changes the form or state of a substance, not its chemical identity. A chemical change, like the rusting of iron, creates a completely new substance (in this case, iron oxide) with new properties.
3. What are some common signs that a chemical change has occurred?
You can often tell a chemical change has occurred by observing one or more of these signs:
- A change in colour (like a fruit ripening).
- The production of a gas (bubbles forming).
- The formation of a solid (known as a precipitate).
- A change in temperature (the substance gets hotter or colder on its own).
- Production of light or sound (like a firework exploding).
4. Can you give some everyday examples of chemical changes?
Yes, chemical changes happen all around us every day! Some common examples include:
- Cooking food, such as frying an egg or baking a cake.
- Digesting food in your stomach.
- Rusting of an iron gate or nail.
- Burning a candle or wood.
- The souring of milk.
5. Why is the rusting of iron considered a chemical change and not a physical one?
Rusting is a classic example of a chemical change because the iron reacts with oxygen and water from the air to form a new substance called iron oxide, which we see as rust. The original shiny, strong iron is gone, and the new flaky, reddish-brown rust has completely different chemical and physical properties. It is not just a change in appearance.
6. How does cooking an egg demonstrate a chemical change?
Cooking an egg is a great example of a chemical change. The heat from the stove causes the proteins in the liquid egg white and yolk to break down and form new, complex structures. This process, called denaturation, is what turns the egg solid and changes its colour. This change is permanent and cannot be easily reversed.
7. Are chemical changes always irreversible?
Most common chemical changes, like burning wood, are considered irreversible because it is very difficult to turn the products back into the original substances. However, not all chemical changes are permanent. Some can be reversed, but it usually requires another chemical reaction to do so.
8. What actually happens to atoms during a chemical change?
During a chemical change, atoms themselves are not created or destroyed. Instead, the bonds holding the atoms together in the original substances are broken, and the atoms rearrange themselves to form new bonds and create new substances. It's like taking apart a structure made of LEGO bricks and using the same bricks to build something entirely new.
