Question

When any of the following changes are observed during the reaction or after the reaction

Answer 1

Answer:

HELLO MATE

the changes are observed both during the reaction and also after the reaction.

Explanation:

ex-you will notice that the h2 gas liberated in any reaction is observed during the reaction and the colour changes in any reaction is observed after reaction.

Answer 2

one of the common changes that is seen before or after a chemical reaction is absorption or liberation of heat energy.

Explanation:

• there are two types of chemical reaction. One type of chemical reaction is known as exothermic reaction
• in case of exothermic reaction there  is liberation of heat due to the chemical reaction. The other type of chemical reaction is known as endothermic reaction. In case of endothermic reaction there is absorption of heat energy by the surrounding. Both type of chemical reaction depend on the type of reactance acting

To know more,

briefly review about India's process in science and technology in ..

.https://brainly.in/question/12166137