In our day to day life, we come across many changes such as rusting of iron, liting of a match, bread becoming toast, etc. All these changes are either a chemical change or a physical change.
Changes can be classified into two types viz physical change and chemical change.
- Physical change is a change in which the molecular arrangements are rearranged and the chemical composition remains as it is. It is usually a reversible process. During a physical change, there is no formation of the new product. Physical properties such as size, color, shape, of the substances changes. Example, freezing of water.
- A chemical change is a change in which the chemical composition of a substance is changed to transform into a new substance. It is usually an irreversible process. Whenever a chemical change occurs it forms a new product. Example, the setting of curd.
You can distinguish between the two as follows:
|Physical Change||Chemical Change|
|No new products formed||New products formed|
Few Important Questions
- Explain if photosynthesis is a chemical or physical change.
- Give two examples for each-
- Physical change
- Chemical change
- Answer true or false-
Formation of manure from leaves is a chemical change.
Condensation of steam is a physical change.
- Fill in the blanks –
Baking soda is chemically known as ___________
A change in which new substance is formed is called ___________ change
- Explain the setting of curd as a chemical change.
- How can we prevent rusting of iron? Explain in detail.
- Distinguish between physical and chemical change.
- Name two methods by which we can prevent the rusting of iron.
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