Chemical and Physical changes




There are several changes we come across daily e.g. dissolving sugar in water, or flattening a metal rod by beating it. These involve changes in the form of the substance. Changes can be classified as:
(i) Physical
(ii) Chemical

Physical properties
Physical properties include size, shape, color and state (solid/liquid/gas) of a substance.

Physical change

  • Any change to the physical properties of a substance is called a physical change.
  • Physical changes are usually reversible as no new substance is formed. It is the same substance but with changed physical properties.

Chemical change

  • A change in which one or more new substances are formed is called as a chemical change.
  • Usually a chemical change involves a chemical reaction, which forms new products.
  • Example : Rusting of Iron, or burning wood.

Kindly refer to the following video for better understanding by Najam academy
You can check what you learned on the following link


Reference
  1. https://sciencenotes.org/wp-content/uploads/2020/10/Chemical-and-Physical-Changes.jpg
  2. https://www.youtube.com/watch?v=-BSJAvNcR0s&t=172s




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