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A site adjacent to the unsaturated carbon atom is called the allylic position or allylic site. A group attached at this site is sometimes described as allylic. Thus, CH 2 =CHCH 2 OH "has an allylic hydroxyl group". Allylic C−H bonds are about 15% weaker than the C−H bonds in ordinary sp 3 carbon centers and are thus more reactive.
The Food Protection Committee started in 1961 to provide objective quality standards for food-grade chemicals. Parts of the first edition were published in loose-leaf form between 1963 and 1966. The scope of the first edition is limited to substances amenable to chemical characterization or biological standardization which are added directly to ...
In general, pK a values in water and organic solvent diverge significantly when the anion is capable of hydrogen bonding. For instance, in the case of water, the values differ dramatically: the pK a in water of water is 14.0, [15] while the pK a in DMSO of water is 31.4, [16] reflecting the differing ability of water and DMSO to stabilize the ...
The IUPAC acknowledges the three divergent definitions of carbonium ion and urges care in the usage of this term. For the remainder of this article, the term carbonium ion will be used in this latter restricted sense, while non-classical carbocation will be used to refer to any carbocation with C–C and/or C–H σ-bonds delocalized by bridging.
An allylic rearrangement or allylic shift is an organic chemical reaction in which reaction at a center vicinal to a double bond causes the double bond to shift to an adjacent pair of atoms: It is encountered in both nucleophilic and electrophilic substitution , although it is usually suppressed relative to non-allylic substitution.
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.
The replaceable plastic bags with a typical volume of 500 or 1000 liters make the container easy to clean and reuse, which is needed for use with food, as strict hygiene regulations must be observed. The space-saving intermediate bulk containers are used in the pharmaceutical, cosmetics and food industries. Several designed have been developed.
An elevated water tank, also known as a water tower, will create a pressure at the ground-level outlet of 1 kPa per 10.2 centimetres (4.0 in) or 1 psi per 2.31 feet (0.70 m) of elevation. Thus a tank elevated to 20 metres creates about 200 kPa and a tank elevated to 70 feet creates about 30 psi of discharge pressure, sufficient for most ...