Maslow's Hierarchy of Needs. Definition. Maslow's hierarchy of needs is a theory of motivation and personality developed by the psychologist Abraham H. Maslow (1908â1970). Maslow's hierarchy explains human behavior in terms of basic requirements for survival and growth.
When you use ice to cool the ingredients for ice cream, the energy is absorbed from the ingredients and from the outside environment (like your hands, if you are holding the baggie of ice!).
When energy is absorbed by the system, Î´E is positive (+). When energy is released from the system, Î´E is negative (â). In this investigation you will explore the energy change associated with evaporation and the differences in evaporation rates of different liquids. Fold a paper towel into thirds.