Chlorofluorocarbons (CFCs) are used generally in aerosols, sprays, perfume, refrigerants, insulation foams and other stuffs. Throughout its applications, the negative impacts weighed more than its benefits. Its greater setback is the contribution to the thinning of the ozone layer which exposes us more with the harmful ultraviolet rays from the sun.
those are all physical changes and most physical changes can be undone like crushing a pice of metal you can flatten it back out you anwser is physical change
