Another possibility is that only a portion of one molecule is transferred to the other molecule. This type of reaction occurs, for example, in redox and acid-base reactions. In redox reactions, the transferred particle is an electron, whereas in acid-base reactions it is a proton.
Psychology is the study of mind and behavior. It is an academic discipline and an applied science which seeks to understand individuals and groups by establishing general principles and researching specific cases.
Psychology is a discipline that has been working on the study of mental processes and behavioral patterns of human beings for over one hundred years. No other mental health discipline can lay claim to such an extensive investigation of the human psyche and this longevity is one of the primary reasons the field of Psychology is held in such high esteem in society in general.