In Britain the unit is spelled carat , just like the weight unit for diamonds and other precious stones. A catalyst is a substance which initiates or facilitates a chemical reaction.
Enzymes are proteins which act as catalysts within the bodies of living plants and animals.
A catalyst has an activity of one katal if it enables a reaction to proceed at the rate of one mole per second. The katal was officially added to the International System at the 21st General Conference of Weights and Measures in October 1999. The unit is often abbreviated K, although this conflicts with the abbreviation for the kelvin. keddah a traditional Egyptian unit of liquid volume, also used in other parts of the Middle East. A keg of herring, for example, contains 60 fish. A keg of nails weighs 100 pounds and thus has a mass of about 45.359 kilograms.