Air-free technique
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Air-free techniques refer to a range of manipulations in the chemistry laboratory for the handling of compounds that are air-sensitive. These techniques prevent the compounds from reacting with compon
An ordinary glovebox, showing the two gloves for manipulation, with airlock on the right.
A Schlenk line with four ports.
A cannula is used to transfer THF from the flask on the right to the flask on the left.
After being refluxed with sodium and benzophenone to remove oxygen and water, toluene is distilled under inert gas into a receiving flask.
Desiccant
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A desiccant is a hygroscopic substance that is used to induce or sustain a state of dryness in its vicinity; it is the opposite of a humectant. Commonly encountered pre-packaged desiccants are solids
Canisters are commonly filled with silica gel and other molecular sieves used as desiccant in drug containers to keep contents dry.
Silica gel in a sachet or porous packet
Toluene is heated under reflux with sodium and benzophenone to produce dry, oxygen-free toluene. The toluene is dry and oxygen free when the intense blue coloration from the benzophenone ketyl radical is observed.