A classmate shows you the remnants of a campfire. He tries to convince you that the ashes in the fire pit are all that remains of the wood that burned. What can
you tell your friend about chemical changes that will help him understand what happened to the matter that made up the wood?

answer: c. the experiment shows that the red substance experienced a chemical change.

explanation: chemical change is the change in which chemical composition of the substance changes. physical change is the change in which there is no change in chemical composition.

chemical changes are accompanied by following changes:

a) precipitate formation

b) energy is released or absorbed

c) formation of bubbles

d) change in color

as it is given that the red color has disappeared and there is production of gas, it means the red substance has undergone a chemical change.

e

its volumetric flask