Question

How can we judge that a change has occurred?

Answer 1

Answer:

We can judge that a change has occurred if the substance changes it's state, color, odour or there is any evolution of gas, pecipitate is formed.

Hope u likes it :D

Answer 2

change occurs when a body changes physically or chemically.

example:

    physical change:melting of ice

     chemical change: formation of precipitate

change can also be reversible and irreversible in nature

example:

            reversible change:melting of ice

            irreversible change:blooming of flowers

sorry for the googled answer last time