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This page contains tables of azeotrope data for various binary and ternary mixtures of solvents. The data include the composition of a mixture by weight (in binary azeotropes, when only one fraction is given, it is the fraction of the second component), the boiling point (b.p.) of a component, the boiling point of a mixture, and the specific gravity of the mixture.
Boiling point (°C) K b (°C⋅kg/mol) Freezing point (°C) K f (°C⋅kg/mol) Data source; ... Acetic Anhydride: 139.0 [6] Ethylene Dichloride: 1.25 83.5 −35 [7 ...
The high reactivity of thiophene toward sulfonation is the basis for the separation of thiophene from benzene, which are difficult to separate by distillation due to their similar boiling points (4 °C difference at ambient pressure). Like benzene, thiophene forms an azeotrope with ethanol.
Because acetic anhydride is not stable in water, the conversion is conducted under anhydrous conditions. To a decreasing extent, acetic anhydride is also prepared by the reaction of ketene with acetic acid at 45–55 °C and low pressure (0.05–0.2 bar). [8] H 2 C=C=O + CH 3 COOH → (CH 3 CO) 2 O (ΔH = −63 kJ/mol)
If the two layers are heated together, the system of layers will boil at 53.3 °C, which is lower than either the boiling point of chloroform (61.2 °C) or the boiling point of water (100 °C). The vapor will consist of 97.0% chloroform and 3.0% water regardless of how much of each liquid layer is present provided both layers are indeed present.
Thiophene-2-acetic acid is the organosulfur compound with the formula HO 2 CCH 2 C 4 H 3 S. Together with thiophene-3-acetic acid, it is one of two isomeric thiophene acetic acids. Preparation and use
Thiophene-3-acetic acid is an organosulfur compound with the formula HO 2 CCH 2 C 4 H 3 S. It is a white solid. It is one of two isomers of thiophene acetic acid, the other being thiophene-2-acetic acid. Thiophene-3-acetic acid has attracted attention as a precursor to functionalized derivatives of polythiophene. [1]
A yellow liquid, it is the more useful of the two isomers of acetylthiophene. It is of commercial interest as a precursor to both thiophene-2-carboxylic acid and thiophene-2-acetic acid. [2] It is prepared by the reaction of thiophene with acetyl chloride in the presence of stannic chloride. [3]