Please please please help with chemistry lab?

so, for a lab i had to heat the following over a bunsen burner in a test tube until a reaction occurred: MAGNESIUM RIBBON, SUCROSE, AMMONIUM DICHROMATE, AND IODINE CRYSTALS. then i have to say if they are PHYSICAL OR CHEMICAL CHANGES. pleaseeee help i hav nooo idea like all of them changed in some form. ALSO, my teacher said there is atleast one of them that exhibited BOTH a physical and chemical change. how is that possible?? and if u hav any idea which one??? thanks any help will be greatly appreciated.