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Pentane-2,4-dione (keto form) Other names ... temperature. 340 °C (644 °F; 613 K) ... In some cases the chelate effect is so strong that no added base is needed to ...
Pentanedione may refer to: Acetylacetone (2,4-pentanedione) Acetylpropionyl (2,3-pentanedione) See also. C 5 H 8 O 2; Cyclopentanedione
In liquids, viscous forces are caused by molecules exerting attractive forces on each other across layers of flow. Increasing temperature results in a decrease in viscosity because a larger temperature means particles have greater thermal energy and are more easily able to overcome the attractive forces binding them together.
George Kleinspehn reported that the Fischer–Fink connectivity could be forced to occur exclusively, by the use of diethyl oximinomalonate in the synthesis, with 2,4-pentanedione, or its 3-alkyl substituted derivatives. Yields were high, around 60%, and this synthesis eventually came to be one of the most important in the repertory. [13]
Temperature-dependency of the heats of vaporization for water, methanol, benzene, and acetone. In thermodynamics, the enthalpy of vaporization (symbol ∆H vap), also known as the (latent) heat of vaporization or heat of evaporation, is the amount of energy that must be added to a liquid substance to transform a quantity of that substance into a gas.
Steric hindrance is often exploited to control selectivity, such as slowing unwanted side-reactions. Steric hindrance between adjacent groups can also affect torsional bond angles . Steric hindrance is responsible for the observed shape of rotaxanes and the low rates of racemization of 2,2'-disubstituted biphenyl and binaphthyl derivatives.
The efficiency of a thermoelectric device for electricity generation is given by , defined as =.. The maximum efficiency of a thermoelectric device is typically described in terms of its device figure of merit where the maximum device efficiency is approximately given by [7] = + ¯ + ¯ +, where is the fixed temperature at the hot junction, is the fixed temperature at the surface being cooled ...
In physics and chemistry, the Nernst effect (also termed the first Nernst–Ettingshausen effect, after Walther Nernst and Albert von Ettingshausen) is a thermoelectric (or thermomagnetic) phenomenon observed when a sample allowing electrical conduction is subjected to a magnetic field and a temperature gradient normal (perpendicular) to each ...