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M N−1. In chemistry, the molar mass (M) (sometimes called molecular weight or formula weight, but see related quantities for usage) of a chemical compound is defined as the ratio between the mass and the amount of substance (measured in moles) of any sample of the compound. [1] The molar mass is a bulk, not molecular, property of a substance.
The molecular mass (m) is the mass of a given molecule. Units of daltons (Da) are often used. [1] Different molecules of the same compound may have different molecular masses because they contain different isotopes of an element. The derived quantity relative molecular mass is the unitless ratio of the mass of a molecule to the atomic mass ...
In polymer chemistry, the molar mass distribution (or molecular weight distribution) describes the relationship between the number of moles of each polymer species (Ni) and the molar mass (Mi) of that species. [1] In linear polymers, the individual polymer chains rarely have exactly the same degree of polymerization and molar mass, and there is ...
Knowing the Mark–Houwink parameters and the molecular weight of one of the polymers allows one to find the molecular weight of the other polymer using a GPC. The GPC sorts the polymer chains by volume and as intrinsic viscosity is related to the volume of the polymer chain, the GPC data is the same for the two different polymers.
In chemistry, the mass fraction of a substance within a mixture is the ratio (alternatively denoted ) of the mass of that substance to the total mass of the mixture. [1] Expressed as a formula, the mass fraction is: tot {\displaystyle w_ {i}= {\frac {m_ {i}} {m_ {\text {tot}}}}.} Because the individual masses of the ingredients of a mixture sum ...
The dispersity (Đ), also known as the polydispersity index (PDI) or heterogeneity index, is a measure of the distribution of molecular mass in a given polymer sample. Đ (PDI) of a polymer is calculated: where is the weight average molecular weight and is the number average molecular weight. is more sensitive to molecules of low molecular mass ...
An equivalent (symbol: officially equiv; [1] unofficially but often Eq[2]) is the amount of a substance that reacts with (or is equivalent to) an arbitrary amount (typically one mole) of another substance in a given chemical reaction. It is an archaic quantity that was used in chemistry and the biological sciences (see Equivalent weight § In ...
Amine value. In organic chemistry, amine value is a measure of the nitrogen content of an organic molecule. [1] Specifically, it is usually used to measure the amine content of amine functional compounds. [2] It may be defined as the number of milligrams of potassium hydroxide (KOH) equivalent to one gram of epoxy hardener resin.