Question

change of state is a physical change not a chemical change justify​

Answer 1

Answer:

change of a state from one form to another form is called physical change. change of one chemical structure to another chemical structure is called chemical state.......

Answer 2

☆Answer :

Change of state is a physical change because they do not change matter's chemical compositions or chemical properties. They are reversible changes. Change of state occurs when matter absorbs or loses energy.

Example : When we melt ice to form water, it changes its state from solid state to liquid state. But the chemical formula of water and ice is still $H_{2}O$. As there is no change in the chemical composition, so it is a physical change.

☆What is physical change ?

=> A process in which a substance change its physical appearance but there is no change in its basic composition is called a physical change.

Example : Melting of ice, magnetisation of iron piece, melting of wax.

In a physical change :

• Only physical properties like colour, appearance of the substance change.
• No new chemical substance is formed.
• Chemical composition and chemical properties of the substance remain unchanged.
• It can often be reversed.

☆What is Chemical change ?

=> A process in which new substances are formed whose properties and composition are different from original substance is called a chemical change. It is also called a chemical reaction.

Example : rusting of iron, digestion of food, burning of paper.

In a chemical change :

• The chemical composition of a substance changes.
• The properties of products formed are very different from properties of reactants.
• Chemical changes are irreversible.
• It is always accompanied by energy change i.e energy is released or absorbed in the form of heat light and electricity.