Effervescence is the escape of gas from an

aqueous solution An aqueous solution is a solution in which the solvent is water. It is mostly shown in chemical equations by appending (aq) to the relevant chemical formula. For example, a solution of table salt, also known as sodium chloride (NaCl), in water ...

and the foaming or fizzing that results from that release. The word effervescence is derived from the

Latin Latin ( or ) is a classical language belonging to the Italic languages, Italic branch of the Indo-European languages. Latin was originally spoken by the Latins (Italic tribe), Latins in Latium (now known as Lazio), the lower Tiber area aroun ...

verb ''fervere'' (to boil), preceded by the adverb ''ex''. It has the same linguistic root as the word

fermentation Fermentation is a type of anaerobic metabolism which harnesses the redox potential of the reactants to make adenosine triphosphate (ATP) and organic end products. Organic molecules, such as glucose or other sugars, are catabolized and reduce ...

. Effervescence can also be observed when opening a bottle of champagne, beer or carbonated beverages such as some carbonated

soft drinks A soft drink (see § Terminology for other names) is a class of non-alcoholic drink, usually (but not necessarily) carbonated, and typically including added sweetener. Flavors used to be natural, but now can also be artificial. The sweet ...

. The visible bubbles are produced by the escape from solution of the dissolved gas (which itself is not visible while dissolved in the liquid).

In beverages

Although CO₂ is most common for beverages,

nitrogen gas Nitrogen is a chemical element; it has symbol N and atomic number 7. Nitrogen is a nonmetal and the lightest member of group 15 of the periodic table, often called the pnictogens. It is a common element in the universe, estimated at seventh i ...

is sometimes deliberately added to certain beers. The smaller bubble size creates a smoother

beer head Beer head (also head or collar) is the frothy foam on top of beer and carbonated beverages which is produced by bubbles of gas, predominantly carbon dioxide, rising to the surface. The elements that produce the head are wort protein, yeast and h ...

. Due to the poor solubility of nitrogen in beer,

keg A keg is a small cask used for storing liquids. Wooden kegs made by a cooper were used to transport nails, gunpowder, and a variety of liquids. Nowadays a keg is normally constructed of stainless steel, although aluminium can be used if it is ...

s or widgets are used for this.

Chemistry

In the laboratory, a common example of effervescence is seen if

hydrochloric acid Hydrochloric acid, also known as muriatic acid or spirits of salt, is an aqueous solution of hydrogen chloride (HCl). It is a colorless solution with a distinctive pungency, pungent smell. It is classified as a acid strength, strong acid. It is ...

is added to a block of

limestone Limestone is a type of carbonate rock, carbonate sedimentary rock which is the main source of the material Lime (material), lime. It is composed mostly of the minerals calcite and aragonite, which are different Polymorphism (materials science) ...

. If a few pieces of

marble Marble is a metamorphic rock consisting of carbonate minerals (most commonly calcite (CaCO3) or Dolomite (mineral), dolomite (CaMg(CO3)2) that have recrystallized under the influence of heat and pressure. It has a crystalline texture, and is ty ...

or an

antacid An antacid is a substance which neutralization (chemistry), neutralizes gastric acid, stomach acidity and is used to relieve heartburn, indigestion, or an upset stomach. Some antacids have been used in the treatment of constipation and diarrhe ...

tablet are put in hydrochloric acid in a

test tube A test tube, also known as a culture tube or sample tube, is a common piece of laboratory glassware consisting of a finger-like length of glass or clear plastic tubing, open at the top and closed at the bottom. Test tubes are usually placed in s ...

fitted with a

bung A stopper, bung, or cork is a cylindrical or conical closure used to seal a container, such as a bottle, tube, or barrel. Description Unlike a lid or bottle cap, which encloses a container from the outside without displacing the inner v ...

, effervescence of

carbon dioxide Carbon dioxide is a chemical compound with the chemical formula . It is made up of molecules that each have one carbon atom covalent bond, covalently double bonded to two oxygen atoms. It is found in a gas state at room temperature and at norma ...

can be witnessed. : This process is generally represented by the following

reaction Reaction may refer to a process or to a response to an action, event, or exposure. Physics and chemistry *Chemical reaction *Nuclear reaction *Reaction (physics), as defined by Newton's third law * Chain reaction (disambiguation) Biology and ...

, where a pressurized dilute solution of

carbonic acid Carbonic acid is a chemical compound with the chemical formula . The molecule rapidly converts to water and carbon dioxide in the presence of water. However, in the absence of water, it is quite stable at room temperature. The interconversion ...

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.G. Liger-Belair ''et al.'', "Study of Effervescence in a Glass of Champagne: Frequencies of Bubble Formation, Growth Rates, and Velocities of Rising Bubbles"
Am. J. Enol. Vitic.
50:3 (1999), 317–323.

References

{{DEFAULTSORT:Effervescence (Chemistry) Chemical processes

In beverages

Chemistry

See also

References