Q. What is scientific law and theory?

A theory is a description that has been supported by many experiments. Theories declare broad principles of nature. Even though theories are the best explanations of phenomena that scientists have at any given time they are always subject to new experimental data and are modified to include new data.

A scientific law explains a relationship in nature that is supported by many experiments and for which no exception has been found. Scientists may perhaps use models and theories to explain why this relationship exists.