In environmental chemistry, the chemical oxygen demand (COD) test is commonly used to indirectly measure the amount of organic compounds in water. Most applications of COD determine the amount of organic pollutants found in surface water (e.g. lakes and rivers) or wastewater, making COD a useful measure of water quality. It is expressed in milligrams per liter (mg/L) also referred to as ppm (parts per million), which indicates the mass of oxygen consumed per liter of solution.
Read more about Chemical Oxygen Demand: Overview, History, Using Potassium Dichromate, Preparation Ferroin Indicator Reagent, Inorganic Interference, Government Regulation
Famous quotes containing the words chemical, oxygen and/or demand:
“Ants are so much like human beings as to be an embarrassment. They farm fungi, raise aphids as livestock, launch armies into war, use chemical sprays to alarm and confuse enemies, capture slaves, engage in child labor, exchange information ceaselessly. They do everything but watch television.”
—Lewis Thomas (b. 1913)
“All the oxygen of the world was in them.
All the feet of the babies of the world were in them.
All the crotches of the angels of the world were in them.
All the morning kisses of Philadelphia were in them.”
—Anne Sexton (1928–1974)
“In our daily intercourse with men, our nobler faculties are dormant and suffered to rust. None will pay us the compliment to expect nobleness from us. Though we have gold to give, they demand only copper.”
—Henry David Thoreau (1817–1862)