Difference Between Physical Change and Chemical Change

In our daily life, we encounter many changes in our surroundings, though we do not notice them, such as souring of milk, rusting of iron, stretching of a rubber band, bread becoming toast, melting of wax, liting of a match, etc. All these changes that take place around us are physical change or chemical change. Physical changes are the changes that change the physical traits of the substance, without making any change in their internal structure.

On the other hand, a chemical change is one that affects the internal structure of the substance, so as to form a new substance. So, take a read of the article to understand the difference between physical change and chemical change.

Content: Physical Change Vs Chemical Change

1. Comparison Chart
2. Definition
3. Key Differences
4. Example of both changes occuring simultaneously
5. Conclusion

Comparison Chart

Basis for Comparison	Physical Change	Chemical Change
Meaning	Physical change refers to a change in which the molecules are rearranged but their internal composition remains same.	Chemical Change is a process in which the substance transforms into a new substance, having different chemical composition.
Example	Tearing of paper, melting/freezing of water, cutting of trees, etc.	Burning of wood/trees/paper, rusting of iron, setting of curd, etc.
Nature	Reversible	Irreversible
Original matter	Can be recovered	Cannot be recovered
Involves	Change in physical properties of the substance, i.e. shape, size, color etc.	Change in chemical properties and composition of the substance.
Product Formation	No new product is formed.	New product is formed.
Energy	Absorption and evolution of energy do not take place.	Absorption and evolution of energy take place, during reaction.

Definition of Physical Change

Physical change is a process in which the substance experiences change in its physical properties like shape, size, colour, volume, appearance, state (i.e. solid, liquid, gas), etc., that, without making any change in their molecular composition. These changes are volatile in; that can be reversed using simple physical methods.

The same element or compound exists prior, or after change, i.e. original characteristics of the object remain unchanged. For example, Melting of wax, boiling of water, dissolving sugar in water, chopping wood, crumpling of paper, etc.

Definition of Chemical Change

Chemical Change is defined as the process in which the atoms of one or more substances are rearranged or combined to form a new substance. When a substance undergoes chemical change, the chemical properties of the substance changes and it is transformed into a different substance with different chemical composition. Evolution of energy, the formation of bubbles, change in odour, change in temperature are some signs of chemical change.

Alternately, known as chemical reaction, wherein the substances involved are known as reactants, and the outcome of the reaction is called product. Energy change is one of the characteristics of a chemical change, because of the formation of the new product. Once the chemical change takes place, it cannot be reversed. For example, adding vinegar to baking soda, bleaching a stain, fermenting of grapes, etc.

Example of both changes occuring simultaneously

• Burning of candle: While melting of wax is a physical change, as the state of the substance changes from solid to liquid, burning of wax is a chemical change, as after consuming energy from wax, light lits up.
• Cooking of food: Cooking of raw vegetables or grains is a chemical change and transformation of water into steam is a physical change.

Conclusion

To sum up, physical change is any change that only transforms the substance’s physical properties, but chemical change results in the change in the chemical structure of the substances involved.