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  2. Elemental analysis - Wikipedia

    en.wikipedia.org/wiki/Elemental_analysis

    [citation needed] This information is important to help determine the structure of an unknown compound, as well as to help ascertain the structure and purity of a synthesized compound. In present-day organic chemistry, spectroscopic techniques ( NMR , both 1 H and 13 C), mass spectrometry and chromatographic procedures have replaced EA as the ...

  3. Prices of chemical elements - Wikipedia

    en.wikipedia.org/wiki/Prices_of_chemical_elements

    This is a list of prices of chemical elements. Listed here are mainly average market prices for bulk trade of commodities. Data on elements' abundance in Earth's crust is added for comparison. As of 2020, the most expensive non-synthetic element by both mass and volume is rhodium.

  4. Lever rule - Wikipedia

    en.wikipedia.org/wiki/Lever_rule

    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.

  5. Criticisms of the labour theory of value - Wikipedia

    en.wikipedia.org/wiki/Criticisms_of_the_labour...

    Thus a 'paper theory of value' would hold that prices were ultimately determined by values, defined as quantities of 'socially necessary paper' (measured in pounds weight). The organic composition of capital would be the ratio of non-paper means of production to paper, and it would be asserted that only paper created new value, and therefore ...

  6. Miscibility - Wikipedia

    en.wikipedia.org/wiki/Miscibility

    Diesel fuel is immiscible in water.The bright rainbow pattern is the result of thin-film interference.. Miscibility (/ ˌ m ɪ s ɪ ˈ b ɪ l ɪ t i /) is the property of two substances to mix in all proportions (that is, to fully dissolve in each other at any concentration), forming a homogeneous mixture (a solution).

  7. Stoichiometry - Wikipedia

    en.wikipedia.org/wiki/Stoichiometry

    Stoichiometry measures these quantitative relationships, and is used to determine the amount of products and reactants that are produced or needed in a given reaction. Describing the quantitative relationships among substances as they participate in chemical reactions is known as reaction stoichiometry. In the example above, reaction ...

  8. Dumas method of molecular weight determination - Wikipedia

    en.wikipedia.org/wiki/Dumas_method_of_molecular...

    Assuming the unknown compound behaves as an ideal gas, the number of moles of the unknown compound, n, can be determined by using the ideal gas law, p V = n R T {\displaystyle pV=nRT\,} where the pressure, p , is the atmospheric pressure , V is the measured volume of the vessel, T is the absolute temperature of the hot bath, and R is the gas ...

  9. Gravimetric analysis - Wikipedia

    en.wikipedia.org/wiki/Gravimetric_analysis

    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 ...