Which of the following is a chemical change?
A. Hydrolysis of a dipeptide.
B. Stretching of a balloon.
C. Freezing of water.
D. Breaking a stick.
I'm pretty sure that the answer is (A), but I'm not 100% positive.
I know that, for (C), you can freeze water, and then you can melt it back to liquid water.
For (D), you can break a stick, and the stick is still now two sticks.
For (B), however, I think that it is a physical change, but I'm not entirely certain.
Can someone please explain this for me?