Sodium carbonate in the context of "Potash"

Sodium bicarbonate (IUPAC name: sodium hydrogencarbonate), commonly known as baking soda or bicarbonate of soda (or simply "bicarb", especially in the UK), or salaratus, is a chemical compound with the formula NaHCO₃. It is a salt composed of a sodium cation (Na) and a bicarbonate anion (HCO−3). 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 sodium carbonate ("washing soda"). The natural mineral form is nahcolite, although it is more commonly found as a component of the mineral trona.

As it has long been known and widely used, the salt has many different names such as baking soda, bread soda, cooking soda, brewing soda and bicarbonate of soda and can often be found near baking powder in stores. The term baking soda is more common in the United States, while bicarbonate of soda is more common in Australia, the United Kingdom, and New Zealand. Abbreviated colloquial forms such as sodium bicarb, bicarb soda, bicarbonate, and bicarb are common.

A soda lake or alkaline lake is a lake on the strongly basic side of neutrality, typically with a pH value between 9 and 12. They are characterized by high concentrations of carbonate salts, typically sodium carbonate (and related salt complexes), giving rise to their alkalinity. In addition, many soda lakes also contain high concentrations of sodium chloride and other dissolved salts, making them saline or hypersaline lakes as well. High pH and salinity often coincide, because of how soda lakes develop. The resulting hypersaline and highly alkaline soda lakes are considered some of the most extreme aquatic environments on Earth.

In spite of their apparent inhospitability, soda lakes are often highly productive ecosystems, compared to their (pH-neutral) freshwater counterparts. Gross primary production (photosynthesis) rates above 10 g C m day (grams of carbon per square meter per day), over 16 times the global average for lakes and streams (0.6 g C m day), have been measured. This makes them the most productive aquatic environments on Earth. An important reason for the high productivity is the virtually unlimited availability of dissolved carbon dioxide.

Alkali, or alkaline, soils are clay soils with high pH (greater than 8.5), a poor soil structure and a low infiltration capacity. Often they have a hard calcareous layer at 0.5 to 1 metre depth. Alkali soils owe their unfavorable physico-chemical properties mainly to the dominating presence of sodium carbonate, which causes the soil to swell and to be difficult to clarify/settle. They derive their name from the alkali metal group of elements, to which sodium belongs, and which can induce basicity. Sometimes these soils are also referred to as alkaline sodic soils. Alkaline soils are basic, but not all basic soils are alkaline.

In metallurgy, a flux is a chemical reducing agent, flowing agent, or purifying agent. Fluxes may have more than one function at a time. They are used in both extractive metallurgy and metal joining. They are named for the ability to make molten metals easier to flow during smelting.

Some of the earliest known fluxes were sodium carbonate, potash, charcoal, coke, borax, lime, lead sulfide and certain minerals containing phosphorus. Iron ore was also used as a flux in the smelting of copper. These agents served various functions, the simplest being a reducing agent, which prevented oxides from forming on the surface of the molten metal, while others absorbed impurities into slag, which could be scraped off molten metal.

Trona (trisodium hydrogendicarbonate dihydrate, also sodium sesquicarbonate dihydrate, Na₂CO₃·NaHCO₃·2H₂O) is a non-marine evaporite mineral. It is mined as the primary source of sodium carbonate in the United States, where it has replaced the Solvay process used in most of the rest of the world for sodium carbonate production. Turkey is also a major producer.

Natron is a naturally occurring mixture of sodium carbonate decahydrate (Na₂CO₃·10H₂O, a kind of soda ash) and around 17% sodium bicarbonate (also called baking soda, NaHCO₃) along with small quantities of sodium chloride and sodium sulfate. Natron is white to colourless when pure, varying to gray or yellow with impurities. Natron deposits are sometimes found in saline lake beds which arose in arid environments. Throughout history natron has had many practical applications that continue today in the wide range of modern uses of its constituent mineral components.

In modern mineralogy the term natron has come to mean only the sodium carbonate decahydrate (hydrated soda ash) that makes up most of the historical salt.

A pretzel (/ˈprɛtsəl/ PRET-səl; from German: Breze or Brezel, pronounced [ˈbʁeːtsl̩] or [ˈbʁɛtsl̩]; Bavarian: Brezn) is a type of baked pastry made from dough that is commonly shaped into a knot. The traditional pretzel shape is a distinctive symmetrical form, with the ends of a long strip of dough intertwined and then twisted back onto itself in a particular way (a pretzel loop or pretzel bow). Today, pretzels come in various shapes, textures, and colors, but the original soft pretzel remains one of the most common pretzel types.

Salt is the most common seasoning, or topping, for pretzels, complementing the washing soda or lye treatment that gives pretzels their traditional skin and flavor acquired through the Maillard reaction. Other toppings are mustard, cheeses, sugar, chocolate, cinnamon, sweet glazing, seeds, and nuts. Regional specialties like Spundekäs have been designed to go along with pretzels. Varieties of pretzels include soft pretzels, which should be eaten shortly after preparation, and hard-baked pretzels, which have a long shelf life.