potassium dichromate

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potassium dichromate

A student carefully weighs potassium dichromate in the chemistry lab.

Definition
  1. Noun:
    • A chemical compound: Potassium dichromate is an inorganic compound with the formula K₂Cr₂O₇. It is a crystalline ionic solid with a bright orange-red color.
    • An oxidizing agent: It is a powerful and commonly used oxidizing agent in various chemical reactions and industrial processes.
    • A source of chromium(VI): It contains chromium in its +6 oxidation state, which gives it its characteristic color and reactive properties.
Usage Examples
  • Noun:
    • The laboratory uses potassium dichromate for cleaning glassware.
    • In the past, potassium dichromate was a key ingredient in certain photographic processes.
    • The bright orange color of the solution is due to dissolved potassium dichromate.
Advanced Usage
  • In analytical chemistry: Potassium dichromate is used as a primary standard in titrations for determining the concentration of reducing agents, such as in the measurement of Chemical Oxygen Demand (COD) in water samples.
    • The COD test involves oxidizing organic matter with potassium dichromate under acidic conditions.
  • In safety contexts: Due to its toxicity and status as a carcinogen and strong oxidizer, its handling requires strict safety protocols.
    • All containers of potassium dichromate must be clearly labeled with hazard warnings.
Variants and Related Words
  • Potassium chromate (n): A related yellow compound with the formula K₂CrO₄, containing chromium(VI).
  • Sodium dichromate (n): A similar orange-red compound, Na₂Cr₂O₇, often used for analogous purposes.
  • Chromium trioxide (n): Another potent chromium(VI) compound, CrO₃, used as an oxidizing agent.
Synonyms
  • Potassium bichromate: An older, synonymous name for the same compound.
  • Dichromic acid, dipotassium salt: A systematic chemical name.
Related Phrases and Terms
  • Oxidizing agent: A substance that can accept electrons from another substance, a key property of potassium dichromate.
  • Hexavalent chromium: Refers to chromium in the +6 oxidation state, which is present in this compound and is a known health hazard.
  • Primary standard: A highly pure compound used for precise quantitative analysis, a role potassium dichromate can serve.
potassium dichromate

A student carefully weighs potassium dichromate in the chemistry lab.

Noun
  1. an orange-red salt used in making dyes and in photography