question: Why is baking soda effective for putting out grease fires?
comment: Burning baking soda releases a non-flamable gas that displaces air and thus helps smothering the flames while also taking some heat off the grease, helping against reignition. But it is only useful for small grease fires. In can cause the burning grease to bubble and splash about.
passages: Section::::Uses.:Cooking.
  
  Section::::Uses.:Cooking.:Leavening.
  
  In cooking, baking soda is primarily used in baking as a leavening agent. When it reacts with acid, carbon dioxide is released, which causes expansion of the batter and forms the characteristic texture and grain in pancakes, cakes, quick breads, soda bread, and other baked and fried foods. Acidic compounds that induce this reaction include phosphates, cream of tartar, lemon juice, yogurt, buttermilk, cocoa, and vinegar. Baking soda may be used together with sourdough, which is acidic, making a lighter product with a less acidic taste.
   Baking soda is still used to soften pulses (peas, beans) before and during cooking, as in the traditional British mushy peas recipe for soaking the peas. The main effect of sodium bicarbonate is to modify the pH of the soaking solution and cooking water, that in turn softens the hard external shell, reduces cooking times and may alter the percentage of nutrients in the dish, its flavour and consistence. 
  
  Baking soda may react with acids in food, including vitamin C (-ascorbic acid).
   Section::::History.:The rise of baking powder.:Eben Norton Horsford.
  
  In America, Eben Norton Horsford, a student of Justus von Liebig, set out to create a flour fortifier and leavening agent. In 1856, he was awarded a patent for "pulverulent phosphoric acid," a process for extracting monocalcium pyrophosphate extracted from bones. Combined with baking soda, monocalcium pyrophosphate provided a double-acting form of leavening. Its initial reaction, when exposed to water, released carbon dioxide and produced dicalcium phosphate, which then reacted under heat to release second-stage carbon dioxide.
   Heat can also by itself cause sodium bicarbonate to act as a raising agent in baking because of thermal decomposition, releasing carbon dioxide. When used this way on its own, without the presence of an acidic component (whether in the batter or by the use of a baking powder containing acid), only half the available CO is released. Additionally, in the absence of acid, thermal decomposition of sodium bicarbonate also produces sodium carbonate, which is strongly alkaline and gives the baked product a bitter, "soapy" taste and a yellow color. To avoid an over-acidic taste from added acid, nonacid ingredients such as whole milk or Dutch-processed cocoa are often added to baked foods.
   The chemical leavening effects were accomplished by the activating of a base such as baking soda in the presence of liquid(s) and an acid such as sour milk, vinegar, lemon juice, or cream of tartar. Because these acidulants react with baking soda quickly, retention of gas bubbles was dependent on batter viscosity. It was critical for the batter to be baked quickly, before the gas escaped. The next step, the development of baking powder, created a system where the gas-producing reactions could be delayed until needed.
  
  Section::::History.:The rise of baking powder.
   As described above, baking powder is mainly just baking soda mixed with an acid. In principle, a number of kitchen acids may be combined with baking soda to simulate commercial baking powders. Vinegar (dilute acetic acid), especially white vinegar, is also a common acidifier in baking; for example, many heirloom chocolate cake recipes call for a tablespoon or two of vinegar. Where a recipe already uses buttermilk or yogurt, baking soda can be used without cream of tartar (or with less). Alternatively, lemon juice can be substituted for some of the liquid in the recipe, to provide the required acidity to activate the baking soda. The main variable with the use of these kitchen acids is the rate of leavening.
   Carbon dioxide production from exposure to heat starts at temperatures above .
  
  Since the reaction occurs slowly at room temperature, mixtures (cake batter, etc.) can be allowed to stand without rising until they are heated in the oven.
  
  Section::::Uses.:Cooking.:Leavening.:Baking powder.
  
  Baking powder, also sold for cooking, contains around 30% of bicarbonate, and various acidic ingredients which are activated by the addition of water, without the need for additional acids in the cooking medium.
   Another typical acid in such formulations is cream of tartar (KCHO), a derivative of tartaric acid.
  
  In some jurisdictions, it is required that baking soda must produce at least 10 per cent of its weight of carbon dioxide. 
  
  Section::::Formulation and mechanism.:Single- and double-acting baking powders.
  
  The use of two acidic components is the basis of the term "double acting." 
  
  The acid in a baking powder can be either fast-acting or slow-acting. 
   The discovery or rediscovery of chemical leavening agents and their widespread military, commercial, and home use in the United States dates back to 1846 with the introduction of commercial baking soda in New York, by Church and Dwight of "Arm & Hammer" fame. This development was extended in 1856 by the introduction of commercial baking powder in Massachusetts, although perhaps the best known form of baking powder is "Calumet", first introduced in Hammond, Indiana and West Hammond, Illinois (later Calumet City, Illinois) in 1889. Both forms of food-grade chemical leaveners are still being produced under their original names, although not within the same corporate structure.
   Chemical leavening agents include a weak base, such as baking soda (sodium bicarbonate) plus a weak acid, such as cream of tartar, lemon juice, or cultured buttermilk, to create an acid–base reaction that releases carbon dioxide. (Quick bread leavened specifically with baking soda is often called "soda bread".) Baking powder contains both an acid and a base in dry powdered form, and simply needs a liquid medium in which to react. Other alternative leavening agents are egg whites mechanically beaten to form stiff peaks, as in the case of many waffle recipes, or steam, in the case of cream puffs. Nevertheless, in a commercial process, designated chemical leavening acids and bases are used to make gas production consistent and controlled. Examples of acid—base combinations include:
   Deflagration systems and products can also be used in mining, demolition and stone quarrying via gas pressure blasting as a beneficial alternative to high explosives.
  
  Section::::Oil/wax fire and water.
  
  Adding water to a burning hydrocarbon such as oil or wax produces a deflagration. The water boils rapidly and ejects the burning material as a fine spray of droplets. A deflagration then occurs as the fine mist of oil ignites and burns extremely rapidly. These are particularly common in chip pan fires, which are responsible for one in five household fires in Britain.
  
  Section::::Flame physics.
   Section::::Formulation and mechanism.
  
  Baking powder is made up of a base, an acid, and a buffering material to prevent the acid and base from reacting before their intended use. 
  
  Most commercially available baking powders are made up of sodium bicarbonate (NaHCO, also known as baking soda or bicarbonate of soda) and one or more acid salts.
  
  Section::::Formulation and mechanism.:Acid-base reactions.
  
  When combined with water, the sodium bicarbonate and acid salts react to produce gaseous carbon dioxide. 
   Unsalted butter is melted over low heat and allowed to separate into butterfat and milk solids. The latter naturally sink to the bottom of the pan and, if left over gentle heat, will begin to brown. As they reach a toasty hazelnut colour, the pan is removed from the heat.
  
  "Beurre noisette" may be used in its liquid state or cooled to a solid form. It has a nutty flavour and is particularly included in the batters for "madeleines" and "financiers".
   Antacid (such as baking soda) solutions have been prepared and used by protesters to alleviate the effects of exposure to tear gas during protests.
   One more type of baking powder was introduced during World War II under the brand name Bakewell. Faced with wartime shortages of cream of tartar and baking powder, Byron H. Smith, a U.S. inventor in Bangor, Maine, created substitute products for American housewives. Bakewell Cream was introduced as a replacement for cream of tartar. It contained sodium acid pyrophosphate and cornstarch and was labeled as a leavening agent. It could be substituted for cream of tartar or mixed with baking soda to replace baking powder.
   BULLET::::- Some methods of preparing olives involve subjecting them to a lye-based brine.
  
  BULLET::::- The Filipino dessert ("kakanin") called "kutsinta" uses a small quantity of lye water to help give the rice flour batter a jelly like consistency. A similar process is also used in the kakanin known as "pitsi-pitsi" or "pichi-pichi" except that the mixture uses grated cassava instead of rice flour.
  
  BULLET::::- The Norwegian dish known as lutefisk (from "lutfisk", "lye fish").
  
  BULLET::::- Bagels are often boiled in a lye solution before baking, contributing to their shiny crust.
   Non-flammable release agents are available and usually classified as combustible.
  
  Section::::Applications.
  
  Section::::Applications.:Asphalt.
   Whether commercially or domestically prepared, the principles behind baking powder formulations remain the same. The acid-base reaction can be generically represented as shown:
  
  The real reactions are more complicated because the acids are complicated. For example, starting with baking soda and monocalcium phosphate the reaction produces carbon dioxide by the following stoichiometry:
  
  A typical formulation (by weight) could call for 30% sodium bicarbonate, 5–12% monocalcium phosphate, and 21–26% sodium aluminium sulfate. 
  
  Alternately, a commercial baking powder might use sodium acid pyrophosphate as one of the two acidic components instead of sodium aluminium sulfate.
   In 1888, William Monroe Wright (a former salesman for Dr. Price) and George Campbell Rew in Chicago introduced a new form of baking powder, which they called Calumet. Calumet Baking Powder contained baking soda, a cornstarch buffer, sodium aluminum sulfate () as a leavening agent, and albumen. In 1899, after years of experimentation with various possible formulae beginning in the 1870s, Herman Hulman of Terre Haute also introduced a baking powder made with sodium aluminium sulfate. He called his baking powder Clabber, referencing a German baking tradition in which soured milk was used for leavening.
   In 1846, the first edition of Catherine Beecher's cookbook "Domestic Recipe Book" (1846) included a recipe for an early prototype of baking powder biscuits that used both baking soda and cream of tartar. 
   Dutch processed cocoa has a neutral pH, and is not acidic like natural cocoa, so in recipes that use baking soda as the leavening agent—which relies on the acidity of the cocoa to activate it—buttermilk, yoghurt or sour milk should be substituted for the milk in the recipe, or a dash of cream of tartar can be used to provide some acidity in the batter. There is no need to add acidity when Dutch process cocoa is used in recipes that use baking powder instead of soda (UK: "bicarb") for leavening.
  
  The Dutch process:
  
  BULLET::::- Lowers acidity
  
  BULLET::::- Increases solubility
   The second step of the Solvay process, heating sodium bicarbonate, is used on a small scale by home cooks and in restaurants to make sodium carbonate for culinary purposes (including pretzels and alkali noodles), as sodium bicarbonate is commonly available as baking soda and the temperatures required ( to ) to convert baking soda to sodium carbonate can be achieved in conventional kitchen ovens.
  
  Section::::Production.:Hou's process.
   Oven cleaners at the time of introduction (1986) were generally similar to Reckitt & Colman's Easy-Off, the leading brand. A strong base, such as caustic soda, attacked grease by saponification. Surfactants attacked both grease and food spills. An abrasive may be present to help scour the oven. The product worked better if the oven was hot, although working in a fairly close space with hot oven cleaner fumes was unpleasant.
   The first to create a form of baking powder was English chemist and food manufacturer Alfred Bird in 1843. Bird was motivated to develop a yeast-free leavener because his wife Elizabeth was allergic to eggs and yeast. His formulation included bicarbonate of soda and tartaric acid, mixed with starch to absorb moisture and prevent the other ingredients from reacting. A single-action form of baking powder, Alfred Bird's Baking Powder reacted as soon as it became damp.
   BULLET::::- Because it is inexpensive, calcium acetate was once a common starting material for the synthesis of acetone before the development of the cumene process:
  
  BULLET::::- A saturated solution of calcium acetate in alcohol forms a semisolid, flammable gel that is much like "canned heat" products such as Sterno. Chemistry teachers often prepare "California Snowballs", a mixture of calcium acetate solution and ethanol. The resulting gel is whitish in color, and can be formed to resemble a snowball.
  