Help with Physical vs Chemical change question?

I'm not quite understanding this part of my lab.



It's asking me which compounds used during the lab went through physical changes or physical changes prior to any chemical changes.



The lab involved using a bunsen burner to heat 3 different compounds in test tubes. So how the hell would there be any physical changes if all I did was put some sample of compound in a test tube, and heated it? When you use a flame on something isn't that automatically a chemical change? So how could there be any physical in the first place?Help with Physical vs Chemical change question?
A physical process is one that can be changed back to its normal state. for example using a bunsen burned to melt an ice cube brings the ice to water. However, you can also freeze the sample again to get ice.



In a chemical process, once you change the composition of the substance you can not go back to get the original composition. An example would be digesting food. Hope this makes sense.Help with Physical vs Chemical change question?
Physical change is the fueling of the fire.
A physical change is one that changes the state of matter, from solid, to liquid, to gas or to plasma.

A chemical reaction is one that changes the makeup of the compound in question, for example freezing oxygen is a physical change, but when hydrogen is added and reacts, making H2O, it makes water.



Hope it clears a few things up.
A physical change occurs if you melt or boil something. It is still the same chemical substance but in a different state of matter.



If you actually burn it (react it with air) or decompose itn (have ths substance break down into new substances), you then have created new chemical substances. This is a chemical change.