8674. Sodium Sesquicarbonate

Nomenclature

CAS number: 533-96-0
Urao; trona.
C2HNa3O6; mol wt 190.00.
C 12.64%, H 0.53%, Na 36.30%, O 50.52%.
Na2CO3.NaHCO3.

Description and references

Found in nature as the dihydrate, e.g., Owens Lake, Searles Lake (U.S.A.); Lake Magadi (Kenya). Produced on a large scale from sodium carbonate and a slight excess of sodium bicarbonate: Schenk in Winnacker-Weingaertner, Chemische Technologie vol. I (München, 1950) p 427.

Derivative

Dihydrate.

Properties

Monoclinic needles, d 2.112. Crystals are stable in air. Soly in water (g/100 ml) at 0°: 13; at 100°: 42. Aq solns are mildly alkaline. pH of 0.1M soln = 10.1.

Caution

Irritating to skin, mucous membranes.

Use

Chiefly in laundering in conjunction with soap.