Is the glass half empty or half full? Is the glass half empty or half full? "Is the glass half empty or half full?" is a common expression, a proverbial phrase, generally used rhetorically to indicate that a particular situation could be a cause for optimism (half full) or pessimism (half empty), or as a general litmus test to simply determine an individual's worldview. The purpose of the question is to demonstrate that the situation may be seen in different ways depending on one's point of view and that there may be opportunity in the situation as well as trouble. Another perspective comes from psychology, where research has
Hammett acidity function H for some concentrated acids: For mixtures (e.g., partly diluted acids in water), the acidity function depends on the composition of the mixture and has to be determined empirically. Graphs of H vs mole fraction can be found in the literature for many acids. Hammett acidity function The Hammett acidity function (H) is a measure of acidity that is used for very concentrated solutions of strong acids, including superacids. It was proposed by the physical organic chemist Louis Plack Hammett and is the best-known acidity function used to extend the measure of Brønsted–Lowry acidity beyond the dilute aqueous solutions for