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  2. Molar concentration - Wikipedia

    en.wikipedia.org/wiki/Molar_concentration

    The concentration of pure osmium tetroxide (molar mass = 254.23 g/mol) is c(OsO 4) = ⁠ 5.1 kg/L / 254.23 g/mol ⁠ = 20.1 mol/L. A typical protein in bacteria, such as E. coli, may have about 60 copies, and the volume of a bacterium is about 10 −15 L. Thus, the number concentration C is C = 60 / (10 −15 L) = 6 × 10 16 L −1. The molar ...

  3. Henderson–Hasselbalch equation - Wikipedia

    en.wikipedia.org/wiki/Henderson–Hasselbalch...

    The Henderson–Hasselbalch equation relates the pH of a solution containing a mixture of the two components to the acid dissociation constant, Ka of the acid, and the concentrations of the species in solution. [2] Simulated titration of an acidified solution of a weak acid (pKa = 4.7) with alkali. To derive the equation a number of simplifying ...

  4. Acid dissociation constant - Wikipedia

    en.wikipedia.org/wiki/Acid_dissociation_constant

    Express each concentration value as the ratio c/c 0, where c 0 is the concentration in a [hypothetical] standard state, with a numerical value of 1, by definition. [19] Express the concentrations on the mole fraction scale. Since mole fraction has no dimension, the quotient of concentrations will, by definition, be a pure number.

  5. Mole fraction - Wikipedia

    en.wikipedia.org/wiki/Mole_fraction

    Mole fraction is numerically identical to the number fraction, which is defined as the number of particles of a constituent N i divided by the total number of all molecules N tot. Whereas mole fraction is a ratio of amounts to amounts (in units of moles per moles), molar concentration is a quotient of amount to volume (in units of moles per litre).

  6. Acid value - Wikipedia

    en.wikipedia.org/wiki/Acid_value

    It is the quantity of base (usually potassium hydroxide (KOH)), expressed as milligrams of KOH required to neutralize the acidic constituents in 1 gram of a sample. [1][2][3][4] The acid value measures the acidity of water-insoluble substances like oils, fats, waxes and resins, which do not have a pH value. The acid number is a measure of the ...

  7. Mass fraction (chemistry) - Wikipedia

    en.wikipedia.org/wiki/Mass_fraction_(chemistry)

    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 ...

  8. Equivalent concentration - Wikipedia

    en.wikipedia.org/wiki/Equivalent_concentration

    For example, sulfuric acid (H 2 SO 4) is a diprotic acid. Since only 0.5 mol of H 2 SO 4 are needed to neutralize 1 mol of OH −, the equivalence factor is: feq (H 2 SO 4) = 0.5. If the concentration of a sulfuric acid solution is c (H 2 SO 4) = 1 mol/L, then its normality is 2 N. It can also be called a "2 normal" solution.

  9. Molar absorption coefficient - Wikipedia

    en.wikipedia.org/wiki/Molar_absorption_coefficient

    In chemistry, the molar absorption coefficient or molar attenuation coefficient (ε) [1] is a measurement of how strongly a chemical species absorbs, and thereby attenuates, light at a given wavelength. It is an intrinsic property of the species. The SI unit of molar absorption coefficient is the square metre per mole (m2/mol), but in practice ...