an analytical process in which a standard solution in a calibrated vessel is added to a measured volume of sample until an end point, such as color change, is reached. From the volume of the sample and the volume of standard solution used, the concentration of a specific material may be calculated.
a decrease in water pressure during flow due to internal friction between molecules of water, and external friction due to irregularities or toughness in surfaces past which the water flows.
the reciprocal of the logarithm of the hydrogen ion concentration. The ph scale is from zero to 14,and 7.0 is the neutral point, indicating the presence of equal concentrations of free hydrogen and hydroxide ions, ph values below 7.0 indicate increasing acidity, and ph values above 7.0 indicate increasing base concentrations.
a permanent, insoluble material which contains ions that will exchange reversibly with other ions in a surrounding solution. Both cation and anion exchangers are used in water conditioning.
an atom, or group of atoms which function as a unit, and has a positive or negative electrical charge, due to the gain or loss of of one or more electrons.
a characteristic of natural water due to the presence of dissolved calcium and magnesium; water hardness is responsible for most scale formation in pipes and water heaters, and forms insoluble" curd" when it reacts with soaps. Hardness is usually expressed in grains per gallon, parts per million, or milligrams per liter, all as calcium carbonate equivalent.
Grain Per Gallon
(gpg) a common basis for reporting water analyses in the U.S. and Canadaone grain per U.S. gallons equals 17.12 milligrams per liter or parts per million. one grain per British gallon equals 14.3 milligrams per liter or parts per million.
(gr.) a unit of weight equal to 1/7000th of a pound, or 0.0648 gram.
specifically, a device or system for the removal of solid particles(suspended solids); in general, includes mechanical, adsorptive, oxidizing, and neutralizing filters.
the point at which a process is stopped because a predetermined value of a measurable variable is reached, the endpoint of an ion exchanger water softener service run is the point at which the hardness of the softener effluent increases to a predefined concentration, often 1.0 grain per gallon; the endpoint of a filter service run may be the point at which the pressure drop across the filter reaches a predetermined value; the endpoint of a titration is the point at which the titrant produces a predetermined color change, ph value, or other measurable characteristic.