Question

Physical changes


A. are only caused through burning a material. B.cannot be detected by the naked eye.
C. do not change the identity of the substance. D.change the identity of a substance.

Answer 1

Physical changes are changes affecting the form of a chemical substance, but not its chemical composition.
A is out cuz burning is not the only method to change it's physical stae.
B is wrong cuz physical changes are seen ! Only the chemical changes aren't seen
C is wrong cuz they do change their identity. Ex: When heat water u get vapor right? LIke wise it changes.
So the answer would be D

Answer 2

Physical change would not change identity of a substance.
A chemical change is the one that changes the identity.
Ice, water, and water vapor all consist of water molecules.
A chemical change would change identity of a substance whether it is a different molecule, flammability, electronegativity, and even including the physical properties too.