Soda Lime


Chemical information

Cal sodada; Calcaria absorbens; Calcaria Compositio; Calx Sodica; Chaux Sodée.
CAS — 8006-28-8.


In Br. Also in USNF.

BP 2008

(Soda Lime). A mixture of sodium hydroxide, or sodium hydroxide and potassium hydroxide, with calcium hydroxide. White or greyish-white granules, or it may be coloured with an indicator to show when its absorptive capacity is exhausted. It absorbs about 20% of its weight of carbon dioxide. Partially soluble in water; almost completely soluble in 1M acetic acid. A suspension in water is strongly alkaline to litmus.


(Soda Lime). A mixture of calcium hydroxide and sodium or potassium hydroxide or both. It may contain an indicator that is inert and that changes colour when the soda lime can no longer absorb carbon dioxide. White or greyish-white granules. May have a colour if an indicator is added.


Soda lime is incompatible with trichloroethylene.


Soda lime is used to absorb carbon dioxide, for instance in closed-circuit anaesthetic apparatus, and in the determination of the basal metabolic rate. Limits are specified for particle size, and particles should be free from dust. Soda lime must not be used with trichloroethylene, since this is decomposed by warm alkali to produce a toxic end product that gives rise to lesions of the nervous system. Soda lime is irritating and corrosive to skin, mucous membranes, and eyes.
Published May 08, 2019.