Would coke turning into a coke-flavored popsicle of coke be a chemical or physical change?

Answer 1

Freezing Coke into a Popsicle would be a physical change. This is because the substance itself isn't changing (the Coke is still Coke, the molecules are just arranged in a slightly different way).

One way to think about the difference between chemical and physical changes is by considering the nature of what you've created by causing the change. For example, by burning paper, you create something completely different than the paper itself: carbon dioxide, some water, and some heat. None of those things even resemble paper, so it's a safe bet that it's a chemical change.

If you were to tear the paper in half, however, you still have paper. Nothing has fundamentally changed about it, you just have a couple pieces now. This is an example of a physical change.

Another way to envision the differences between chemical and physical changes is to consider how to reverse the change. In most cases, if the change can be easily reversed, it is a physical change. In your case, to change the Coke Popsicle back into Coke, you'd simply have to heat it back up. In the case of frying an egg, it's impossible to unfry it. This is a good indication that a chemical change has taken place.

Formally, a physical change is any change that does not affect the substance's chemical identity. A chemical change is a change in which bonds are broken and/or formed, changing the chemical identity of the substance.