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  2. Urea - Wikipedia

    en.wikipedia.org/wiki/Urea

    The structure of the molecule of urea is O=C(−NH 2) 2.The urea molecule is planar when in a solid crystal because of sp 2 hybridization of the N orbitals. [8] [9] It is non-planar with C 2 symmetry when in the gas phase [10] or in aqueous solution, [9] with C–N–H and H–N–H bond angles that are intermediate between the trigonal planar angle of 120° and the tetrahedral angle of 109.5°.

  3. Ureas - Wikipedia

    en.wikipedia.org/wiki/Ureas

    Biotin, a water-soluble B vitamin, is a bicyclic urea.. In chemistry, ureas are a class of organic compounds with the formula (R 2 N) 2 CO where R = H, alkyl, aryl, etc. Thus, in addition to describing the specific chemical compound urea ((H 2 N) 2 CO), urea is the name of a functional group that is found in many compounds and materials of both practical and theoretical interest.

  4. EPA list of extremely hazardous substances - Wikipedia

    en.wikipedia.org/wiki/EPA_list_of_extremely...

    This is the list of extremely hazardous substances defined in Section 302 of the U.S. Emergency Planning and Community Right-to-Know Act (42 U.S.C. § 11002). The list can be found as an appendix to 40 CFR 355. [1] Updates as of 2006 can be seen on the Federal Register, 71 FR 47121 (August 16, 2006). [2]

  5. Metabolic waste - Wikipedia

    en.wikipedia.org/wiki/Metabolic_waste

    The excretion of urea is called ureotelism. Land animals, mainly amphibians and mammals, convert ammonia into urea, a process which occurs in the liver and kidney. These animals are called ureotelic. [3] Urea is a less toxic compound than ammonia; two nitrogen atoms are eliminated through it and less water is needed for its excretion.

  6. Commodity chemicals - Wikipedia

    en.wikipedia.org/wiki/Commodity_chemicals

    There have been several studies of the scale and complexity of this market for example in the USA. [1] [2] Commodity chemicals are a sub-sector of the chemical industry (other sub sectors are fine chemicals, specialty chemicals, inorganic chemicals, petrochemicals, pharmaceuticals, renewable energy (e.g. biofuels) and materials (e.g ...

  7. Organic matter - Wikipedia

    en.wikipedia.org/wiki/Organic_matter

    Organic matter, organic material, or natural organic matter refers to the large source of carbon-based compounds found within natural and engineered, terrestrial, and aquatic environments. It is matter composed of organic compounds that have come from the feces and remains of organisms such as plants and animals . [ 1 ]

  8. Chemical impurity - Wikipedia

    en.wikipedia.org/wiki/Chemical_impurity

    Firstly, a pure chemical should appear in at least one chemical phase and can also be characterized by its phase diagram. Secondly, a pure chemical should prove to be homogeneous (i.e., a uniform substance that has the same composition throughout the material [2]). The perfect pure chemical will pass all attempts to separate and purify it further.

  9. Chemical hazard - Wikipedia

    en.wikipedia.org/wiki/Chemical_hazard

    Chemical hazards are usually classified separately from biological hazards (biohazards). Chemical hazards are classified into groups that include asphyxiants, corrosives, irritants, sensitizers, carcinogens, mutagens, teratogens, reactants, and flammables. [1] In the workplace, exposure to chemical hazards is a type of occupational hazard.