Parts Per Million

Science / Chemistry / Parts Per Million: Concentration expressed as parts of solute per million parts of solution. Usually refers to parts per million by mass. For example, a 10 ppm nacl solution can be written as: 10 mg nacl/kg solution, 10 ?µg nacl/g solution, 10 ng nacl/mg solution. In very dilute aqueous solutions, ppm is approximately equal to mg solute per liter of solution.

Parts Per Billion (PPB)

Business / Real Estate / Parts Per Billion (PPB): Units commonly used to express contamination ratios, as in establishing the maximum permissible amount of a contaminant in water, land, or air. These ratios can also be expressed in parts per million MORE


Science / Chemistry / Permanganate: Permanganate ion (mno4-) is a powerful oxidizing agent used in chemical analysis and water treatment. The ion has an intense purple color. MORE

Permanent Vegetative Cover

Business / Agriculture / Permanent Vegetative Cover: Trees, or perennial grasses, legumes, or shrubs with an expected life span of at least 5 years. Permanent cover is required on cropland entered into the Conservation Reserve Program. MORE