Effervescence

Although CO2 is most common for beverages, nitrogen gas is sometimes deliberately added to certain beers. The smaller bubble size creates a smoother beer head. Due to the poor solubility of nitrogen in beer, kegs or widgets are used for this. == Chemistry ==

In the laboratory, a common example of effervescence is seen if hydrochloric acid is added to a block of limestone. If a few pieces of marble or an antacid tablet are put in hydrochloric acid in a test tube fitted with a bung, effervescence of carbon dioxide can be witnessed. : This process is generally represented by the following reaction, where a pressurized dilute solution of carbonic acid in water releases gaseous carbon dioxide at decompression: : In simple terms, it is the result of the chemical reaction occurring in the liquid which produces a gaseous product. ==See also==