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Zeolite exhibited in the Estonian Museum of Natural History. Zeolite is a group of several microporous, crystalline aluminosilicate minerals commonly used as commercial adsorbents and catalysts. [1] They mainly consist of silicon, aluminium, oxygen, and have the general formula M n+ 1/n (AlO 2) − (SiO 2) x ･y H 2 O where M n+ 1/n is either ...
The molar gas constant (also known as the gas constant, universal gas constant, or ideal gas constant) is denoted by the symbol R or R. It is the molar equivalent to the Boltzmann constant , expressed in units of energy per temperature increment per amount of substance , rather than energy per temperature increment per particle .
Faujasite (FAU-type zeolite) is a mineral group in the zeolite family of silicate minerals.The group consists of faujasite-Na, faujasite-Mg and faujasite-Ca. They all share the same basic formula (Na 2,Ca,Mg) 3.5 [Al 7 Si 17 O 48]·32(H 2 O) by varying the amounts of sodium, magnesium and calcium. [1]
Pentasil-zeolites are defined by their structure type, and more specifically by their X-ray diffraction patterns. ZSM -5 is the trade name of a pentasil-zeolite. As early as 1967, Argauer and Landolt worked out parameters for the synthesis of pentasilzeolites, particularly those relating to the following molar ratios: OH − /SiO 2 = 0.07–10, SiO 2 /Al 2 O 3 = 5–100, H 2 O/SiO 2 = 1–240. [1]
The van der Waals equation of state may be written as (+) =where is the absolute temperature, is the pressure, is the molar volume and is the universal gas constant.Note that = /, where is the volume, and = /, where is the number of moles, is the number of particles, and is the Avogadro constant.
gas molecules only interact with adjacent layers; and; the Langmuir theory can be applied to each layer. the enthalpy of adsorption for the first layer is constant and greater than the second (and higher). the enthalpy of adsorption for the second (and higher) layers is the same as the enthalpy of liquefaction. The resulting BET equation is
The relative activity of a species i, denoted a i, is defined [4] [5] as: = where μ i is the (molar) chemical potential of the species i under the conditions of interest, μ o i is the (molar) chemical potential of that species under some defined set of standard conditions, R is the gas constant, T is the thermodynamic temperature and e is the exponential constant.
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]