As I am a grade 9 student, please use simple English that does not involve many technical words in Chemistry. Thank you.
I have learnt from my teachers' handout that physical methods of separation include heating, and that a compound can only be broken down into elements by chemical methods such as electrolysis.
But why can mercury oxide (a compound) be decomposed into mercury and oxygen upon heating (physical method)?
Or is it simply because heating is a chemical method? (that my teacher probably was mistaken)