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The amine value is useful in helping determine the correct stoichiometry of a two component amine cure epoxy resin system. [6] [7] [8]It is the number of Nitrogens x 56.1 (Mwt of KOH) x 1000 (convert to milligrams) divided by molecular mass of the amine functional compound.
The accurate mass (more appropriately, the measured accurate mass [9]) is an experimentally determined mass that allows the elemental composition to be determined. [10] For molecules with mass below 200 Da , 5 ppm accuracy is often sufficient to uniquely determine the elemental composition.
The Dumas method of molecular weight determination was historically a procedure used to determine the molecular weight of an unknown volatile substance. [ 1 ] [ 2 ] The method was designed by the French chemist Jean Baptiste André Dumas , after whom the procedure is now named.
Gravimetric analysis describes a set of methods used in analytical chemistry for the quantitative determination of an analyte (the ion being analyzed) based on its mass. The principle of this type of analysis is that once an ion's mass has been determined as a unique compound, that known measurement can then be used to determine the same analyte's mass in a mixture, as long as the relative ...
In chemistry, the lever rule is a formula used to determine the mole fraction (x i) or the mass fraction (w i) of each phase of a binary equilibrium phase diagram.It can be used to determine the fraction of liquid and solid phases for a given binary composition and temperature that is between the liquidus and solidus line.
The molecular mass of a polymer differs from typical molecules, in that polymerization reactions produce a distribution of molecular weights and shapes. The distribution of molecular masses can be summarized by the number-average molecular weight, weight-average molecular weight, and polydispersity.
The Avogadro constant, commonly denoted N A [1] or L, [2] is an SI defining constant with an exact value of 6.022 140 76 × 10 23 mol −1 (reciprocal moles). [3] [4] It defines the number of constituent particles in one mole, where the particles in question can be either molecules, atoms, ions, ion pairs, or any other elementary entities.
Conventional mass is defined as follows: "For a mass at 20 °C, 'conventional mass' is the mass of a reference standard of density 8,000 kg/m 3 which it balances in air with a density of 1.2 kg/m 3." The effect is a small one, 150 ppm for stainless steel mass standards, but the appropriate corrections are made during the manufacture of all ...