This is a law. That is because it cannot be refuted in any way. A theory often depends on perfect conditions. Even simple theories often are based on perfect conditions that cannot be found on earth. Unlike it, laws are applicable no matter where and how you are. Such are for example Newton's laws or laws of thermodynamics.
<span> matter is neither created nor destroyed in any chemical change this is law because law is undenieable and it is obvious.it is based on observations hypothesis and experiments it can not be prooven wrong where as theory can be prooven wrong</span>
