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A cooling bath or ice bath, in laboratory chemistry practice, is a liquid mixture which is used to maintain low temperatures, typically between 13 °C and −196 °C. These low temperatures are used to collect liquids after distillation , to remove solvents using a rotary evaporator , or to perform a chemical reaction below room temperature ...
Ice: Sodium chloride-20 1 to 3 ratio of salt to ice. Dry ice: Tetrachloroethylene-22 Dry ice: Carbon Tetrachloride-23 Dry ice: 1,3-Dichlorobenzene-25 Dry ice: o-Xylene-29 Liquid N 2: Bromobenzene-30 Dry ice: m-Toluidine-32 Dry ice: 3-Heptanone-38 Ice: Calcium chloride hexahydrate -40 1 to 0.8 ratio of salt to ice. Dry ice: Acetonitrile-41 Dry ...
In chemistry, a condenser is laboratory apparatus used to condense vapors – that is, turn them into liquids – by cooling them down. [1] Condensers are routinely used in laboratory operations such as distillation, reflux, and extraction. In distillation, a mixture is heated until the more volatile components boil off, the vapors are ...
Freeze drying, also known as lyophilization or cryodesiccation, is a low temperature dehydration process [1] that involves freezing the product and lowering pressure, thereby removing the ice by sublimation. [2] This is in contrast to dehydration by most conventional methods that evaporate water using heat. [3]
In practice, a mechanical freezing process is usually used instead due to cost. There has been continuous optimization of the freezing rate in mechanical freezing to minimize ice crystal size. [2] Flash freezing techniques are also used to freeze biological samples quickly so that large ice crystals cannot form and damage the sample. [5]
In chemistry a cooling bath may be used to control the temperature of a strongly exothermic reaction. A frigorific mixture may be used as an alternative to mechanical refrigeration. For example to fit two machined metal parts together, one part is placed in a frigorific mixture, causing it to contract so that may be easily inserted into the ...
A cold finger is a piece of laboratory equipment that is used to generate a localized cold surface. It is named for its resemblance to a finger and is a type of cold trap . The device usually consists of a chamber that a coolant fluid (cold tap water, or perhaps something colder) can enter and leave.
The desired product, benzoic acid (3), is obtained by the following work-up: [2] Synthesis of benzoic acid with work-up step in red. The reaction mixture containing the Grignard reagent is allowed to warm to room temperature in a water bath to allow excess dry ice to evaporate. Any remaining Grignard reagent is quenched by the addition of water.