Calcium carbonate (Chalk) is a chemical compound, with the ...



Calcium carbonate (Chalk) is a chemical compound, with the chemical formula CaCO3. It is a common substance found as rock in all parts of the world, and is the main component of shells of marine organisms, snails, and eggshells. Calcium carbonate is the active ingredient in agricultural lime, and is usually the principal cause of hard water. It is commonly used medicinally as a calcium supplement or as an antacid.

Sodium bicarbonate (Baking Soda) is the chemical compound with the formula NaHCO3. Since it has long been known and is widely used, the salt has many other names including baking soda, bread soda, cooking soda, bicarb soda, bicarbonate of soda, sodium hydrogen carbonate or sodium bicarbarbonate. The word saleratus, from Latin sal æratus meaning "aerated salt", was widely used in the 19th century for both sodium bicarbonate and potassium bicarbonate. The term has now fallen out of common usage.

Sodium bicarbonate is a white solid that is crystalline but often appears as a fine powder. It has a slight alkaline taste resembling that of washing soda (sodium carbonate). It is a component of the mineral natron and is found dissolved in many mineral springs. Sodium bicarbonate can be used as a wash to remove any acidic impurities from a "crude" liquid, producing a more pure sample.

Cornstarch, or cornflour, is the starch of the maize grain, commonly known as corn. It is also ground from the endosperm, or white heart, of the corn kernel. It has a distinctive appearance and feel when mixed raw with water or milk, giving easily to gentle pressure but resisting sudden pressure (see Non-Newtonian fluid). It is usually included as an anti-caking agent in powdered sugar (10X or confectioner's sugar). For this reason, recipes calling for powdered sugar often call for at least light cooking to remove the raw cornstarch taste. Cornstarch is often used as a binder in puddings and similar foods. Most of the packaged pudding mixes available in grocery stores include cornstarch. Cornstarch puddings can be made at home easily by using a double boiler. The most basic such pudding is made from from milk, sugar, cornstarch and a flavoring agent.

Cornstarch can be used as a thickener in many recipes. Because cornstarch tends to form lumps when mixed with warm or hot water, it is best dissolved in cold water. It is also found in many gluten-free recipes.

Sugar (the word stems from the Sanskrit sharkara) consists of a class of edible crystalline substances including sucrose, lactose, and fructose. Human taste buds interpret its flavor as sweet. Sugar as a basic food carbohydrate primarily comes from sugar cane and from sugar beet, but also appears in fruit, honey, sorghum, sugar maple (in maple syrup), and in many other sources. It forms the main ingredient in much candy. "Excessive" consumption of sugar has been associated[1] with increased incidences of type 2 diabetes, of obesity and of tooth decay. In non-scientific use, the term sugar refers to sucrose (also called "table sugar" or "saccharose") — a white crystalline solid disaccharide. In this informal sense, the word "sugar" principally refers to crystalline sugars.

Humans most commonly use sucrose as their sugar of choice for altering the flavor and properties (such as mouthfeel, preservation, and texture) of beverages and food. Commercially produced table sugar comes either from sugar cane or from sugar beet. Manufacturing and preparing food may involve other sugars, including palm sugar and fructose, generally obtained from corn (maize) or from fruit.

Sugar may dissolve in water to form a syrup. A great many foods exist which principally contain dissolved sugar. Generically known as "syrups", they may also have other more specific names such as "honey" or "molasses".

Vinegar is a liquid processed from the fermentation of ethanol in a process that yields its key ingredient, acetic acid. The acetic acid concentration ranges typically from 4 to 8 percent by volume for table vinegar [1] (typically 5%) and higher concentrations for pickling (up to 18%) although in some countries the minimum strength may be less. Natural vinegars also contain smaller amounts of tartaric acid, citric acid, and other acids. The pH of vinegar is typically in the range of 2.5 to 3, depending on the concentration of acetic acid. Commercially available vinegar usually has a pH of about 2.

Vinegar has a density of approximately 0.96 g/mL. The density level depends on the acidity of the vinegar. Vinegar is made from the oxidation of ethanol in wine, cider, beer, fermented fruit juice, or nearly any other liquid containing alcohol. Commercial vinegar is produced either by fast or slow fermentation processes. Slow methods are generally used with traditional vinegars and fermentation proceeds slowly over the course of weeks or months. The longer fermentation period allows for the accumulation of a nontoxic slime composed of acetic acid bacteria and soluble cellulose, known as the mother of vinegar. Fast methods add mother of vinegar (i.e. bacterial culture) to the source liquid and then add air using a venturi pump system or a turbine to promote oxygenation to give the fastest fermentation. In fast production processes, vinegar may be produced in a period ranging from 20 hours to three days.

Iodine is a chemical element that has the symbol I and atomic number 53. Naturally-occurring iodine is a single isotope with 74 neutrons.

Chemically, iodine is the least reactive of the halogens, and the most electropositive halogen after astatine. However, the element does not occur in the free state in nature. As with all other halogens (members of Group VII in the Periodic Table), when freed from its compounds iodine forms diatomic molecules (I2). Iodine under standard conditions is a dark-purple/dark-brown solid. It can be seen apparently subliming at standard temperatures into a violet-pink gas that has an irritating odor. This halogen forms compounds with many elements, but is less reactive than the other members of its Group VII (halogens) and has some metallic light reflectance.

Water is a common chemical substance that is essential for the survival of all known forms of life.[1] In typical usage, water refers only to its liquid form or state, but the substance also has a solid state, ice, and a gaseous state, water vapor. Water can appear in three phases. Water takes many different forms on Earth: water vapor and clouds in the sky; seawater and rarely icebergs in the ocean; glaciers and rivers in the mountains; and aquifers in the ground. Water can dissolve many different substances, giving it different tastes and odors. In fact, humans and other animals have developed senses to be able to evaluate the potability of water: animals generally dislike the taste of salty sea water and the putrid swamps and favor the purer water of a mountain spring or aquifer. Humans also tend to prefer cold water rather than lukewarm, as cold water is likely to contain less microbes. The taste advertised in spring water or mineral water derives from the minerals dissolved in it, as pure H2O is tasteless. As such, purity in spring and mineral water refers to purity from toxins, pollutants, and microbes.

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