PROPERTIES OF CARBONIC ACID*

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CARBONIC ACID.

PART LXXXII.

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Carbonic acid exists, in the gazeous state, at common tem-peratures, and at any pressure of the atmosphere which weknow of. It is therefore a permanent, elastic, aeriform fluid,and has been considered as such under the' article carbonicacid gas, vol. I. p. 234, to which we refer the reader for a fulleraccount of it.

The combination of carbonic acid with different bases, con-stitutes CARBONATES.

PROPERTIES OF CARBONATES.

Carbonates produce a rapid effervescence when mixed withsulphuric, nitric, muriatic, &c. acids. Most of them are decom-posable by heat. Some of them are insoluble in water, but be-come soluble by an excess of carbonic acid. Several of thealcaline carbonates change vegetable blues to green, and have analcaline taste.