Are you unclear about the difference between physical changes and chemical changes and the way to tell them apart? In a nutshell, a chemical change creates a new substance, while a physical change doesn't. A material may alter forms or shapes while going through a physical change, however no chemical reactions happen and no new compounds are produced.
Examples of Physical
melting an ice cube
crumpling a sheet of paper
breaking a bottle
casting silver in a mold
Examples of Chemical
dissolving salt in water
mixing acid and base
Compare and Contrast Physical and Chemical
1. Physical changes modify physical properties of a
substance. These contain melting, breaking and dissolving. Generally, physical
changes are effortlessly reversible. The physical look may change, however the
chemical composition stays the same. Chemical changes, however, change the
substance into something totally different. For instance, when something rusts,
the metal reacts with oxygen, building a compound that looks like neither the
metal nor oxygen: rust
2. As you go from gas to liquid to solid, movement on the
molecular level reduces. Thus, the molecules in gas move all over, however in
the molecules in a solid stay mostly in the identical place.
3. In a chemical reaction,
energy can either be absorbed (endothermic rxn) or released (exothermic rxn).