Search results
Results from the WOW.Com Content Network
The short ton (abbreviation tn[ 1 ]) is a measurement unit equal to 2,000 pounds (907.18 kg). It is commonly used in the United States, where it is known simply as a ton;[ 1 ] however, the term is ambiguous, the single word " ton " being variously used for short, long, and metric tons. The various tons are defined as units of mass. [ 2 ]
For convenience in avoiding conversions in the imperial (or US customary units), some engineers adopted the pound-mole (notation lb-mol or lbmol), which is defined as the number of entities in 12 lb of 12 C. One lb-mol is equal to 453.592 37 g‑mol, [25] which is the same numerical value as the number of grams in an international avoirdupois ...
In chemistry, a formula unit is the smallest unit of a non-molecular substance, such as an ionic compound, covalent network solid, or metal. [1][2] It can also refer to the chemical formula for that unit. Those structures do not consist of discrete molecules, and so for them, the term formula unit is used. In contrast, the terms molecule or ...
Such scales are used to make the most accurate of fine measurements, such as in the needs of empirical chemistry. Avoirdupois (/ ˌævərdəˈpɔɪz, ˌævwɑːrdjuːˈpwɑː /; [ 1 ] abbreviated avdp.) [ 2 ] is a measurement system of weights that uses pounds and ounces as units. [ 3 ][ 4 ] It was first commonly used in the 13th century AD and ...
Stoichiometry is not only used to balance chemical equations but also used in conversions, i.e., converting from grams to moles using molar mass as the conversion factor, or from grams to milliliters using density. For example, to find the amount of NaCl (sodium chloride) in 2.00 g, one would do the following:
Turnover number. In chemistry, the term " turnover number " has two distinct meanings. In enzymology, the turnover number (kcat) is defined as the limiting number of chemical conversions of substrate molecules per second that a single active site will execute for a given enzyme concentration [ET] for enzymes with two or more active sites. [1 ...
For example, the conversion factor between a mass fraction of 1 ppb and a mole fraction of 1 ppb is about 4.7 for the greenhouse gas CFC-11 in air (Molar mass of CFC-11 / Mean molar mass of air = 137.368 / 28.97 = 4.74). For volume fraction, the suffix "V" or "v" is sometimes appended to the parts-per notation (e.g. ppmV, ppbv, pptv).
A chemical equation is the symbolic representation of a chemical reaction in the form of symbols and chemical formulas.The reactant entities are given on the left-hand side and the product entities are on the right-hand side with a plus sign between the entities in both the reactants and the products, and an arrow that points towards the products to show the direction of the reaction. [1]