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  2. Theoretical oxygen demand - Wikipedia

    en.wikipedia.org/wiki/Theoretical_oxygen_demand

    Theoretical oxygen demand (ThOD) is the calculated amount of oxygen required to oxidize a compound to its final oxidation products. [1] However, there are some differences between standard methods that can influence the results obtained: for example, some calculations assume that nitrogen released from organic compounds is generated as ammonia, whereas others allow for ammonia oxidation to ...

  3. Chemical oxygen demand - Wikipedia

    en.wikipedia.org/wiki/Chemical_oxygen_demand

    C = Concentration of oxidizable compound in the sample, FW = Formula weight of the oxidizable compound in the sample, RMO = Ratio of the # of moles of oxygen to # of moles of oxidizable compound in their reaction to CO 2, water, and ammonia. For example, if a sample has 500 Wppm (Weight Parts per Million) of phenol: C 6 H 5 OH + 7O 2 → 6CO 2 ...

  4. Total organic carbon - Wikipedia

    en.wikipedia.org/wiki/Total_organic_carbon

    Total organic carbon (TOC) is an analytical parameter representing the concentration of organic carbon in a sample. TOC determinations are made in a variety of application areas. For example, TOC may be used as a non-specific indicator of water quality, or TOC of source rock may be used as one factor in evaluating a petroleum play. [1]

  5. Elemental analysis - Wikipedia

    en.wikipedia.org/wiki/Elemental_analysis

    Antoine Lavoisier is regarded as the inventor of elemental analysis as a quantitative, experimental tool to assess the chemical composition of a compound. At the time, elemental analysis was based on the gravimetric determination of specific absorbent materials before and after selective adsorption of the combustion gases.

  6. Calibration curve - Wikipedia

    en.wikipedia.org/wiki/Calibration_curve

    A calibration curve plot showing limit of detection (LOD), limit of quantification (LOQ), dynamic range, and limit of linearity (LOL).. In analytical chemistry, a calibration curve, also known as a standard curve, is a general method for determining the concentration of a substance in an unknown sample by comparing the unknown to a set of standard samples of known concentration. [1]

  7. Henderson–Hasselbalch equation - Wikipedia

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

    C A is the analytical concentration of the acid and C H is the concentration the hydrogen ion that has been added to the solution. The self-dissociation of water is ignored. A quantity in square brackets, [X], represents the concentration of the chemical substance X. It is understood that the symbol H + stands for the hydrated hydronium ion.

  8. Defining equation (physical chemistry) - Wikipedia

    en.wikipedia.org/wiki/Defining_equation...

    Theoretical chemistry requires quantities from core physics, such as time, volume, temperature, and pressure.But the highly quantitative nature of physical chemistry, in a more specialized way than core physics, uses molar amounts of substance rather than simply counting numbers; this leads to the specialized definitions in this article.

  9. Thermodynamic activity - Wikipedia

    en.wikipedia.org/wiki/Thermodynamic_activity

    The relative activity of a species i, denoted a i, is defined [4] [5] as: = where μ i is the (molar) chemical potential of the species i under the conditions of interest, μ o i is the (molar) chemical potential of that species under some defined set of standard conditions, R is the gas constant, T is the thermodynamic temperature and e is the exponential constant.