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  2. Potassium dichromate - Wikipedia

    en.wikipedia.org/wiki/Potassium_dichromate

    When heated strongly, it decomposes with the evolution of oxygen. 4 K 2 Cr 2 O 7 → 4 K 2 CrO 4 + 2 Cr 2 O 3 + 3 O 2 When an alkali is added to an orange-red solution containing dichromate ions, a yellow solution is obtained due to the formation of chromate ions ( CrO 2− 4 ).

  3. Potassium chromate - Wikipedia

    en.wikipedia.org/wiki/Potassium_chromate

    Two crystalline forms are known, both being very similar to the corresponding potassium sulfate. Orthorhombic β-K 2 CrO 4 is the common form, but it converts to an α-form above 666 °C. [ 1 ] These structures are complex, although the chromate ion adopts the typical tetrahedral geometry.

  4. Chromium(VI) oxide peroxide - Wikipedia

    en.wikipedia.org/wiki/Chromium(VI)_oxide_peroxide

    The generally yellow chromates or orange dichromates turn to dark blue as "chromium(VI) oxide peroxide" forms: CrO 2− 4 + 2 H 2 O 2 + H + → [CrO(O 2) 2 OH] − + 3 H 2 O. The structure of the pyridine complex has been determined crystallographically. [2] Adducts with other N-heterocycles have also been characterized similarly. [3]

  5. Solubility chart - Wikipedia

    en.wikipedia.org/wiki/Solubility_chart

    The following chart shows the solubility of various ionic compounds in water at 1 atm pressure and room temperature (approx. 25 °C, 298.15 K). "Soluble" means the ionic compound doesn't precipitate, while "slightly soluble" and "insoluble" mean that a solid will precipitate; "slightly soluble" compounds like calcium sulfate may require heat to precipitate.

  6. Metal aquo complex - Wikipedia

    en.wikipedia.org/wiki/Metal_aquo_complex

    In the absence of isotopic labeling, the reaction is degenerate, meaning that the free energy change is zero. Rates vary over many orders of magnitude. Rates vary over many orders of magnitude. The main factor affecting rates is charge: highly charged metal aquo cations exchange their water more slowly than singly charged cations.

  7. Thermal decomposition - Wikipedia

    en.wikipedia.org/wiki/Thermal_decomposition

    When water is heated to well over 2,000 °C (2,270 K; 3,630 °F), a small percentage of it will decompose into OH, monatomic oxygen, monatomic hydrogen, O 2, and H 2. [3] The compound with the highest known decomposition temperature is carbon monoxide at ≈3870 °C (≈7000 °F). [citation needed]

  8. Hydrothermal synthesis - Wikipedia

    en.wikipedia.org/wiki/Hydrothermal_synthesis

    Hydrothermal synthesis can be defined as a method of synthesis of single crystals that depends on the solubility of minerals in hot water under high pressure. The crystal growth is performed in an apparatus consisting of a steel pressure vessel called an autoclave, in which a nutrient is supplied along with water. A temperature gradient is ...

  9. Thermophoresis - Wikipedia

    en.wikipedia.org/wiki/Thermophoresis

    An example that may be observed by the naked eye with good lighting is when the hot rod of an electric heater is surrounded by tobacco smoke: the smoke goes away from the immediate vicinity of the hot rod. As the small particles of air nearest the hot rod are heated, they create a fast flow away from the rod, down the temperature gradient.