EXERCISE 1. (ABOUT CHEMISTRY)

DEAR ALL MY STUDENT

YOU HAVE ALREADY KNOW THAT IF WE BURN A PIECE OF PAPER AT THE END WE CAN GET THE DUST OF PAPER WHERE IN THE MIDLLE OF RECTION WE CAN SEE THE BALCK OF BURNING THAT IS THE CARBON  FROM THE PAPER . THE PHENOMENA LIKE THIS WE CAN CALL LIKE CHEMICAL REACTION .

AND NOW I LIKE YOU TO ANSWER MY QUESTION HERE :

1. WHAT THE MEANING OF CHEMICAL REACTION ? THAT THE DIFFERENCE WITH PHYSICAL REACTION OR PHYSICAL CHANGES  ?

YOU CAN GIVE ANOTHER EXAMPLES ABOUT WHAT IS CHEMICAL CHANGE ITSELF !