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
Alkalinity given in the unit mEq/L (milliequivalent per liter). Commercially, as in the swimming pool industry, alkalinity might also be given in parts per million of equivalent calcium carbonate (ppm CaCO). Alkalinity is sometimes incorrectly used interchangeably with basicity. For example, the addition of CO lowers the pH of a solution. This increase reduces the basicity; however, the alkalinity remains unchanged (see example below).For total alkalinity testing, N/10 HSO is used by hydrologists along with phenolphthalein indicator. In typical groundwater or seawater, the measured alkalinity is set equal to: Alkalinity can be measured by titrating a sample with a strong acid