In our daily life, many changes take place around us. Some changes can be undone and the original substance can be obtained again, while some changes are permanent and cannot be reversed. Based on this, changes are classified into reversible changes and irreversible changes.
Reversible Changes:
Reversible changes are changes that can be reversed to get back the original substance. In these changes, no new substance is formed, only the form or state of the substance changes. These changes are usually temporary and can go back and forth by changing conditions like heating or cooling.
Examples of Reversible Changes
- Melting of ice: Ice changes into water when heated, and water changes back into ice when cooled.
- Freezing of water: Water changes into ice when cooled, and ice can melt back into water when heated.
- Melting of wax: Wax becomes liquid on heating and solidifies again on cooling.
Irreversible Changes:
Irreversible changes are changes that cannot be reversed to get back the original substance. In these changes, new substances are formed, and the change is permanent. Once it happens, the original material cannot be recovered.
Examples of Irreversible Changes
- Cooking food: Raw food changes into cooked food and cannot return to its raw form.
- Making popcorn: Heating corn kernels makes them burst into popcorn, which cannot become kernels again.
- Burning of paper: Paper changes into ash and gases, which cannot be reversed back into paper.
Difference Between Reversible and Irreversible Changes:
| Reversible Changes | Irreversible Changes |
|---|---|
| Can be reversed | Cannot be reversed |
| No new substance is formed | New substance is formed |
| Temporary change | Permanent change |
| Example: melting ice | Example: cooking food |