Physical Change vs. Chemical Change
Teaching Science to a nine year old can make you learn some deep lessons yourself. We spoke about matter today and the fact that it is made up of molecules. We also discussed the various states of matter namely solid, liquid and gas. We then talked about the difference between physical change and chemical change of matter.
Physical change is defined as a change in matter, where only its physical form changes but the molecules remain the same. For example, cutting a paper into two pieces. Chemical change on the other hand, is a change where the molecules of the matter themselves change. For example, burning the paper makes it into ash. Paper has created a new substance called ash by changing its chemical composition.
I asked Toyna to give me another example of the same. She rushed to a world map pasted on her room wall and said, “This is India, here. This was Andhra Pradesh! They cut Andhra Pradesh into two parts. Now it is two states. This is a physical change. It does not change the molecules (the people) of the state in any way! So it is not a chemical change.”
It took me couple of seconds to soak in what she said. She looked at me to see my response and give her an affirmation that she was right. In scientific theory, I am pretty sure this example is not correct. But then, this is so so true in something which is even above science. Wow! I am still trying to digest this example and see the world from where she sees it.
(Illustration of a space rocket by Toyna, where the kite is actually flying higher than the rocket itself.)