Sodium sesquicarbonate

Description

White, needle-shaped crystals. Sodium sesquicarbonate occurs in nature as Trona. It is generally used as a water softener and mildly alkaline cleaner. Sodium sesquicarbonate was recommended in the 1970s as a stabilization treatment of corroded bronze and iron objects. However, more recent examinations indicate that bronze pieces treated with sesquicarbonate are later susceptible to the formation of Chalconatronite corrosion products.

Synonyms and Related Terms

urao; trona

Risks

• Skin contact causes irritation.
• Hill Brothers: SDS

Physical and Chemical Properties

Soluble in water (pH = 10.1 for a 0.1 molar solution).

Composition	Na2CO3-NaHCO3-2H2O
CAS	553-96-0
Density	2.112 g/ml
Molecular Weight	mol. wt. = 190.0

Resources and Citations

• W.A.Oddy, M.J.Hughes "The Stabilization of Active Bronze and Iron Antiquities by the use of Sodium Sesquicarbonate" Studies in Conservation, 15:183-189, 1970.

• C. Horie, J.Vint, "Chalconatronite: A By-Product of Conservation?" Studies in Conservation, 27:185-186, 1982.

• Richard S. Lewis, Hawley's Condensed Chemical Dictionary, Van Nostrand Reinhold, New York, 10th ed., 1993

• The Merck Index, Martha Windholz (ed.), Merck Research Labs, Rahway NJ, 10th edition, 1983 Comment: entry 8823