Baking soda is extremely versatile. In the kitchen, it is used in baking as a raising agent (also called leavening agent), and around the house it works as a general-purpose cleaner. It can also be used as a medicine to prevent heartburn.
From Wikipedia: “Sodium bicarbonate (IUPAC name: sodium hydrogen carbonate) is a chemical compound with the formula NaHCO3. It is a salt composed of sodium ions and bicarbonate ions. Sodium bicarbonate is a white solid that is crystalline but often appears as a fine powder. It has a slightly salty, alkaline taste resembling that of washing soda (sodium carbonate). The natural mineral form is nahcolite. It is a component of the mineral natron and is found dissolved in many mineral springs. It is among the food additives encoded by the European Union, identified as E 500.”
“Sodium bicarbonate, referred to as baking soda, is primarily used in baking, as a leavening agent. It reacts with acidic components in batters, releasing carbon dioxide, 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. Natural acids in sourdough can be leavened with the addition of small amounts as well.
Heat can also independently cause sodium bicarbonate to act as a raising agent by releasing carbon dioxide when used in baking. When used on its own, only half the available CO2 is released. Additionally, without an acid added to baking soda, sodium carbonate is produced that is strongly alkaline and gives the baked product a bitter, "soapy" taste and a yellow color. Baking powder differs in that it includes an acid which is activated by the addition of water. Carbon dioxide production from exposure to heat starts at temperatures above 80 °C.”
Pest control “Used to kill cockroaches. Once consumed, it causes internal organs of cockroaches to burst due to gas collection. Sodium bicarbonate can be an effective way of controlling fungal growth, and in the United States is registered by the Environmental Protection Agency as a biopesticide.”
Paint and corrosion removal “Sodium bicarbonate is used in a process for removing paint and corrosion called sodablasting; the process is particularly suitable for cleaning aluminium panels which can be distorted by other types of abrasive.”
“It can be administered to pools, spas, and garden ponds to raise the total alkalinity, this will also raise the pH level and make maintaining proper pH easier. In the event that the pH is low and the alkalinity is adequate or high, Baking Soda (sodium bicarbonate) should not be used to adjust the pH.”
Pyrotechnics “Sodium bicarbonate is one of the main components of the common incendiary "black snake" firework. The effect is caused by the thermal decomposition, which produces carbon dioxide gas to produce a long snake-like ash as a combustion product of the other main component, sucrose.”
Fire extinguisher “Sodium bicarbonate can be used to extinguish small grease or electrical fires by being thrown over the fire, as heating of sodium bicarbonate releases carbon dioxide. However, it should not be applied to fires in deep fryers; the sudden release of gas may cause the grease to splatter. Sodium bicarbonate is used in BC dry chemical fire extinguishers as an alternative to the more corrosive diammonium phosphate in ABC extinguishers. The alkaline nature of sodium bicarbonate makes it the only dry chemical agent, besides Purple-K, that was used in large-scale fire suppression systems installed in commercial kitchens. Because it can act as an alkali, the agent has a mild saponification effect on hot grease, which forms a smothering, soapy foam.”
Neutralisation of acids and bases “Sodium bicarbonate is amphoteric, reacting with acids and bases. It reacts violently with acids, releasing CO2 gas as a reaction product. It is commonly used to neutralize unwanted acid solutions or acid spills in chemical laboratories.
A wide variety of applications follows from its neutralisation properties, including reducing the spread of white phosphorus from incendiary bullets inside an afflicted soldier's wounds.”
“Sodium bicarbonate mixed with water can be used as an antacid to treat acid indigestion and heartburn. Its reaction with stomach acid produces salt, water, and carbon dioxide:
NaHCO3 + HCl → NaCl + H2O + CO2 (g)”