Sodium sesquicarbonate

Sodium sesquicarbonate
Identifiers
3D model (JSmol)
ECHA InfoCard 100.007.802 Edit this at Wikidata
EC Number
  • 208-580-9
UNII
  • InChI=1S/2CH2O3.3Na/c2*2-1(3)4;;;/h2*(H2,2,3,4);;;/q;;3*+1/p-3
    Key: WCTAGTRAWPDFQO-UHFFFAOYSA-K
  • C(=O)(O)[O-].C(=O)([O-])[O-].[Na+].[Na+].[Na+]
Properties
Na3H(CO3)2·2H2O
Appearance white, needle-like
Density 2.112 g/cm3 (dihydrate)
dihydrate
13 g/100 mL (0 °C)
42 g/100 mL (100 °C)
1.5073 (dihydrate)
Structure
monoclinic (dihydrate)
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).

Sodium sesquicarbonate (systematic name: trisodium hydrogendicarbonate) Na3H(CO3)2 is a double salt of sodium bicarbonate and sodium carbonate (NaHCO3 · Na2CO3), and has a needle-like crystal structure. However, the term is also applied to an equimolar mixture of those two salts, with whatever water of hydration the sodium carbonate includes, supplied as a powder.

The dihydrate, Na3H(CO3)2 · 2H2O, occurs in nature as the evaporite mineral trona.[1]

Due to concerns about the toxicity of borax which was withdrawn as a cleaning and laundry product, sodium sesquicarbonate is sold in the European Union (EU) as "Borax substitute".[2] It is also known as one of the E number food additives E500(iii).

  1. ^ "Trona".
  2. ^ "Borax substitute – laundry booster, multi purpose cleaner, bath soak". Dri-Pak. 27 April 2015. Archived from the original on 2 July 2019. Retrieved 28 May 2017.