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  2. Potassium dichromate - Wikipedia

    en.wikipedia.org/wiki/Potassium_dichromate

    Potassium dichromate, K 2 Cr 2 O 7, is a common inorganic chemical reagent, most commonly used as an oxidizing agent in various laboratory and industrial applications. As with all hexavalent chromium compounds, it is acutely and chronically harmful to health.

  3. Chemical oxygen demand - Wikipedia

    en.wikipedia.org/wiki/Chemical_oxygen_demand

    Of these, potassium dichromate (K 2 Cr 2 O 7) is the most effective: it is relatively cheap, easy to purify, and can nearly completely oxidize almost all organic compounds. In these methods, a fixed volume with a known excess amount of the oxidant is added to a sample of the solution being analyzed.

  4. Atmospheric pressure - Wikipedia

    en.wikipedia.org/wiki/Atmospheric_pressure

    Atmospheric pressure, also known as air pressure or barometric pressure (after the barometer), is the pressure within the atmosphere of Earth. The standard atmosphere (symbol: atm) is a unit of pressure defined as 101,325 Pa (1,013.25 hPa ), which is equivalent to 1,013.25 millibars , [ 1 ] 760 mm Hg , 29.9212 inches Hg , or 14.696 psi . [ 2 ]

  5. Dobson unit - Wikipedia

    en.wikipedia.org/wiki/Dobson_unit

    The Dobson unit arises from the ideal gas law =, where P and V are pressure and volume respectively, and n, R and T are the number of moles of gas, the gas constant (8.314 J/(mol·K)), and T is temperature in kelvins (K). The number density of air is the number of molecules or atoms per unit volume:

  6. Oxidizing agent - Wikipedia

    en.wikipedia.org/wiki/Oxidizing_agent

    The international pictogram for oxidizing chemicals. Dangerous goods label for oxidizing agents. An oxidizing agent (also known as an oxidant, oxidizer, electron recipient, or electron acceptor) is a substance in a redox chemical reaction that gains or "accepts"/"receives" an electron from a reducing agent (called the reductant, reducer, or electron donor).

  7. Chromic acid cell - Wikipedia

    en.wikipedia.org/wiki/Chromic_acid_cell

    Bichromate cells. Left - single fluid, right - two fluid. The chromic acid cell is a type of primary cell which uses chromic acid as a depolarizer.The chromic acid is usually made by acidifying (with sulfuric acid) a solution of potassium dichromate.

  8. Biochemical oxygen demand - Wikipedia

    en.wikipedia.org/wiki/Biochemical_oxygen_demand

    The sample is kept in a sealed container fitted with a pressure sensor. A substance that absorbs carbon dioxide (typically lithium hydroxide) is added in the container above the sample level. The sample is stored in conditions identical to the dilution method. Oxygen is consumed and, as ammonia oxidation is inhibited, carbon dioxide is released.

  9. Chromyl chloride - Wikipedia

    en.wikipedia.org/wiki/Chromyl_chloride

    Chromyl chloride can be prepared by the reaction of potassium chromate or potassium dichromate with hydrogen chloride in the presence of concentrated sulfuric acid, followed by distillation. [3] [4] K 2 Cr 2 O 7 + 6 HCl → 2 CrO 2 Cl 2 + 2 KCl + 3 H 2 O. The sulfuric acid serves as a dehydration agent.