Glossary of physics and chemistry theme 2

-Every form of matter with its own clear boundaries is called a physical body.

-every form of matter without its own morphology and whose boundaries are imprecise is called a physical system.

-Direct observation: This requires the use of the correct instruments,  such as optical,  microscopic or the more modern,  scanning tunneling microscope .

-Indirect observation: Through observable experimental evidence at the scale we can derive models and establish laws and theories that describe the behaviour matter at a microscopic level