If an atom loses or gains an electron, it is called
a. ion
b. isotope
c. molecule

the principles and empirical processes of discovery and demonstration considered characteristic of or necessary for scientific investigation, generally involving the observation of phenomena, the formulation of a hypothesis concerning the phenomena, experimentation to test the hypothesis, and development of a conclusion that confirms, rejects, or modifies the hypothesis.

the tricuspid valve is present between right atrium and right ventricle