Nitrogen, drying with phosphorus oxygen-free

The needed apparatus and chemicals are placed in the dry box, and the box is closed and thoroughly flushed with dry oxygen-free nitrogen. When in use, it is kept under a small nitrogen pressure so that air will not diffuse into the box. A dish containing phosphorus pentoxide is often placed inside the dry box to ensure that moisture is removed, and if it is particularly important to remove all traces of water and oxygen, a dish containing the liquid sodium-potassium alloy may be placed inside the box. This alloy must, however, be handled with considerable care, for it will bum in air and will react explosively with water. 

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