Chemical Change

A new substance is produced.

The product i.e. the substance formed as a result of chemical change has different properties than the original substance.

The change is usually difficult to reverse.

The amount of energy absorbed or released during the change is usually large.

Examples of Chemical changes.

Burning is a chemical change in which the substance that burns combines with oxygen in the air; heat and light energy are given out.

The rusting of iron is a chemical change which produces the new substance rust - known to the chemist as hydrated oxide of iron.

The digestion of a meal involves a long series of chemical changes. The complex substances we eat are changed into simpler substances.

Respiration is a complete cycle of chemical changes in which the body uses oxygen to release the chemical energy trapped inside food.

Energy Released/Absorbed

Changes in which energy is released are:

1. Burning

2. Respiration

3. Condensation

Changes in which energy is absorbed are:

1. Melting of Ice

2. Cooking of Food

3. Boiling of water

Access All Content

Video Explanations, Practice Worksheets and Solved Examples for all Chapters.
Textbook solutions, Formulae and Mindmaps across all boards.

More from Grade 6 Chemistry


Combining, reacting, exploding and much more. Learn what all elements can do with their atoms!


Learn about the element twins, radicals, and how they react!

Chemical Formula

Chemical Formula is the language of Chemistry. Learn how to write the chemical formula of a compound from valencies of the elements using the criss-cross method.