sodium carbonate

American  

noun

Chemistry.

1. Also called soda ash.  an anhydrous, grayish-white, odorless, water-soluble powder, Na 2 CO 3 , usually obtained by the Solvay process and containing about 1 percent of impurities consisting of sulfates, chlorides, and bicarbonates of sodium: used in the manufacture of glass, ceramics, soaps, paper, petroleum products, sodium salts, as a cleanser, for bleaching, and in water treatment.

2. Also called sal soda, soda, washing soda.  the decahydrated form of this salt, Na 2 CO 3 ⋅10H 2 O, used similarly.

3. the monohydrated form of this salt, Na 2 CO 3 ⋅H 2 O, used similarly, especially in photography.

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sodium carbonate British  

noun

1. a colourless or white odourless soluble crystalline compound existing in several hydrated forms and used in the manufacture of glass, ceramics, soap, and paper and as an industrial and domestic cleansing agent. It is made by the Solvay process and commonly obtained as the decahydrate (washing soda or sal soda) or a white anhydrous powder (soda ash). Formula: Na 2 CO 3 See also washing soda sal soda soda ash

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Etymology

Origin of sodium carbonate

First recorded in 1865–70

Compare meaning

How does sodium-carbonate compare to similar and commonly confused words? Explore the most common comparisons:

• sodium carbonate vs. sodium bicarbonate

Example Sentences

See Examples For:

sodium carbonate

During the reaction, sodium hydroxide captures carbon released from the plastics and converts it into solid sodium carbonate.

From Science Daily ● Jul. 31, 2026

The Met's Cdr Jon Savell said a laboratory analysis of the substance from the attack site found it was a "very strong concentrated corrosive substance, either liquid sodium hydroxide or liquid sodium carbonate".

From BBC ● Feb. 4, 2024

The two carbonates used commercially in the largest quantities are sodium carbonate and calcium carbonate.

From Textbooks ● Feb. 14, 2019

He’s something of a health nut who avoids chemicals, even such harmless ones as sodium carbonate.

From Washington Post ● Aug. 4, 2016

Dissolve the sodium carbonate and borax in water and when dissolved add the glycerine and stir.

From Soap-Making Manual A Practical Handbook on the Raw Materials, Their Manipulation, Analysis and Control in the Modern Soap Plant. by E. G. Thomssen