Difference Between Chemical Change and Physical Change
When it comes to changes that occur in matter, there are two main categories: physical changes and chemical changes. While both types of changes involve modifications to the properties of matter, they differ in significant ways. In this article, we’ll explore the differences between chemical change and physical change.
Physical Change
Physical change refers to a change in the physical properties of matter without a change in its chemical composition. This means that the molecules of the substance remain the same, but their arrangement or form may have changed. Examples of physical changes include changes in state (e.g., melting, freezing, vaporization, and condensation), changes in shape or size, and changes in color.
An easy way to identify a physical change is to observe if the chemical composition has remained the same. For instance, when water is frozen, it doesn’t change its chemical composition. It’s still H2O – the same molecules like before, just in a different state.
Chemical Change
A chemical change, on the other hand, involves a change in the chemical composition of the substance. In other words, the substance changes into a different kind of matter with its own unique set of properties. During a chemical change, the original molecules are broken down and reformed into new molecules with different properties.
Chemical changes typically involve the formation or breaking of chemical bonds, which leads to the creation of new substances. Examples of chemical changes include combustion, oxidation, and the reaction of acids with bases to form salts and water.
An example of a chemical change can be seen when hydrogen and oxygen gases react to form water. This change involves the breaking of chemical bonds in the hydrogen and oxygen molecules and the formation of a new substance, water.
Conclusion
In conclusion, physical changes involve modifications to the physical properties of a substance without changing its chemical composition. Whereas, chemical changes involve the formation of new substances and the loss of the original properties of the matter. Understanding the differences between physical change and chemical change is essential not only for science students but also for anyone who wants to have a basic understanding of chemistry.
Table difference between chemical change and physical change
| Property | Chemical Change | Physical Change |
|---|---|---|
| Definition | A change that results in the formation of new substances with new physical and chemical properties. | A change that only affects the physical properties of a substance, such as its shape, size or state of matter, but does not result in the formation of a new substance. |
| Examples | Burning wood, rusting of iron, cooking food, digestion, photosynthesis. | Melting ice, boiling water, dissolving sugar in water, crushing a can, bending a wire. |
| Energy Change | Often releases or absorbs energy, such as heat or light. | May involve a change in energy, but usually does not release or absorb energy. |
| Reversibility | Generally irreversible or difficult to reverse. | Generally reversible or easy to reverse. |
| Chemical Formula | May involve a change in the chemical formula of the substances involved. | The chemical formula of the substance(s) involved remains the same. |