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  2. Ebullioscopic constant - Wikipedia

    en.wikipedia.org/wiki/Ebullioscopic_constant

    M is the molar mass of the solvent. T b is boiling point of the pure solvent in kelvin. ΔH vap is the molar enthalpy of vaporization of the solvent. Through the procedure called ebullioscopy, a known constant can be used to calculate an unknown molar mass. The term ebullioscopy means "boiling measurement" in Latin.

  3. Boltzmann constant - Wikipedia

    en.wikipedia.org/wiki/Boltzmann_constant

    Boltzmann constant: The Boltzmann constant, k, is one of seven fixed constants defining the International System of Units, the SI, with k = 1.380 649 x 10 −23 J K −1.The Boltzmann constant is a proportionality constant between the quantities temperature (with unit kelvin) and energy (with unit joule).

  4. Molecular-weight size marker - Wikipedia

    en.wikipedia.org/wiki/Molecular-weight_size_marker

    The range of a particular marker refers to variety of bands it can map. A "high" range refers to relatively large fragments (measured in kb) while a "low" range refers to markers that distinguish between small fragments (measured in bp). Some markers can even be described as "ultra-low range", [16] but even more precise is the microRNA marker ...

  5. Molar mass - Wikipedia

    en.wikipedia.org/wiki/Molar_mass

    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.

  6. Reaction rate constant - Wikipedia

    en.wikipedia.org/wiki/Reaction_rate_constant

    where A and B are reactants C is a product a, b, and c are stoichiometric coefficients,. the reaction rate is often found to have the form: = [] [] Here ⁠ ⁠ is the reaction rate constant that depends on temperature, and [A] and [B] are the molar concentrations of substances A and B in moles per unit volume of solution, assuming the reaction is taking place throughout the volume of the ...

  7. Planck units - Wikipedia

    en.wikipedia.org/wiki/Planck_units

    Several quantities are not "extreme" in magnitude, such as the Planck mass, which is about 22 micrograms: very large in comparison with subatomic particles, and within the mass range of living organisms. [20]: 872 Similarly, the related units of energy and of momentum are in the range of some everyday phenomena.

  8. Cryoscopic constant - Wikipedia

    en.wikipedia.org/wiki/Cryoscopic_constant

    Through cryoscopy, a known constant can be used to calculate an unknown molar mass. The term "cryoscopy" means "freezing measurement" in Greek . Freezing point depression is a colligative property , so Δ T depends only on the number of solute particles dissolved, not the nature of those particles.

  9. Mass fraction (chemistry) - Wikipedia

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

    Mass fraction can also be expressed, with a denominator of 100, as percentage by mass (in commercial contexts often called percentage by weight, abbreviated wt.% or % w/w; see mass versus weight). It is one way of expressing the composition of a mixture in a dimensionless size ; mole fraction (percentage by moles , mol%) and volume fraction ...