Sodium hexametaphosphate SHMP
Sodium hexametaphosphate (SHMP) is a salt of composition Na6[(PO3)6]. Sodium hexametaphosphate of commerce is typically a mixture of metaphosphates (empircal formula: NaPO3), of which the hexamer is one, and is usually the compound referred to by this name. Such a mixture is more correctly termed sodium polymetaphosphate. They are white solids that dissolve in water.
Uses
SHMP is used as a sequestrant and has applications within a wide variety of industries, including as a food additive in which it is used under the E number E452i. Sodium carbonate is sometimes added to SHMP to raise the pH to 8.0–8.6, which produces a number of SHMP products used for water softening and detergents.
A significant use for sodium hexametaphosphate is as a deflocculant in the production of clay-based ceramic particles. It is also used as a dispersing agent to break down clay and other soil types for soil texture assessment.
It is used as an active ingredient in toothpastes as an anti-staining and tartar prevention ingredient.
Sodium Hydrosulfite
Sodium dithionite (also known as sodium hydrosulfite) is a white crystalline powder with a weak sulfurous odor. Although it is stable in the absence of air, it decomposes in hot water and in acid solutions.
Structure
Raman spectroscopy and single-crystal X-ray diffraction studies reveal that the geometry of the dithionite anion is flexible. The dithionite dianion has C 2 symmetry, with almost eclipsed with a 16° O-S-S-O torsional angle. In the dihydrated form the dithionite anion has a shorter S-S bond length and a gauche 56° O-S-S-O torsional angle.
A weak S-S bond is indicated by the S-S distance of 239 pm. Because this bond is fragile, the dithionite anion dissociates in solution into the [SO2]− radical anion, as has been confirmed by EPR spectroscopy. It is also observed that 35S undergoes rapid exchange between S2O42− and SO2 in neutral or acidic solution, consistent with the weak S-S bond in the anion.
Preparation
Sodium dithionite is produced industrially by reduction of sulfur dioxide. Several methods are employed, including reduction with zinc powder, sodium borohydride, and formate. Approximately 300,000 tons were produced in 1990.
Sodium Hydrosulfite
Sodium dithionite (also known as sodium hydrosulfite) is a white crystalline powder with a weak sulfurous odor. Although it is stable in the absence of air, it decomposes in hot water and in acid solutions.
Structure
Raman spectroscopy and single-crystal X-ray diffraction studies reveal that the geometry of the dithionite anion is flexible. The dithionite dianion has C 2 symmetry, with almost eclipsed with a 16° O-S-S-O torsional angle. In the dihydrated form the dithionite anion has a shorter S-S bond length and a gauche 56° O-S-S-O torsional angle.
A weak S-S bond is indicated by the S-S distance of 239 pm. Because this bond is fragile, the dithionite anion dissociates in solution into the [SO2]− radical anion, as has been confirmed by EPR spectroscopy. It is also observed that 35S undergoes rapid exchange between S2O42− and SO2 in neutral or acidic solution, consistent with the weak S-S bond in the anion.
Preparation
Sodium dithionite is produced industrially by reduction of sulfur dioxide. Several methods are employed, including reduction with zinc powder, sodium borohydride, and formate. Approximately 300,000 tons were produced in 1990.
Sodium hydroxide
Sodium hydroxide, also known as lye and caustic soda, is an inorganic compound with the formula NaOH. It is a white solid ionic compound consisting of sodium cations Na+ and hydroxide anions
Sodium hydroxide is a highly caustic base and alkali that decomposes proteins at ordinary ambient temperatures and may cause severe chemical burns. It is highly soluble in water, and readily absorbs moisture and carbon dioxide from the air. It forms a series of hydrates NaOH·nH 2O.The monohydrate NaOH·H 2O crystallizes from water solutions between 12.3 and 61.8 °C. The commercially available "sodium hydroxide" is often this monohydrate, and published data may refer to it instead of the anhydrous compound. As one of the simplest hydroxides, it is frequently utilized alongside neutral water and acidic hydrochloric acid to demonstrate the pH scale to chemistry students.
Sodium hydroxide is used in many industries: in the manufacture of pulp and paper, textiles, drinking water, soaps and detergents, and as a drain cleaner. Worldwide production in 2004 was approximately 60 million tonnes, while demand was 51 million tonnes.
Sodium hydroxide
Sodium hydroxide, also known as lye and caustic soda, is an inorganic compound with the formula NaOH. It is a white solid ionic compound consisting of sodium cations Na+ and hydroxide anions OH−
Sodium hydroxide is a highly caustic base and alkali that decomposes proteins at ordinary ambient temperatures and may cause severe chemical burns. It is highly soluble in water, and readily absorbs moisture and carbon dioxide from the air. It forms a series of hydrates NaOH·nH 2O. The monohydrate NaOH·H 2O crystallizes from water solutions between 12.3 and 61.8 °C. The commercially available "sodium hydroxide" is often this monohydrate, and published data may refer to it instead of the anhydrous compound. As one of the simplest hydroxides, it is frequently utilized alongside neutral water and acidic hydrochloric acid to demonstrate the pH scale to chemistry students.
Sodium hydroxide is used in many industries: in the manufacture of pulp and paper, textiles, drinking water, soaps and detergents, and as a drain cleaner. Worldwide production in 2004 was approximately 60 million tonnes, while demand was 51 million tonnes.
Sodium hydroxide
Pure sodium hydroxide is a colorless crystalline solid that melts at 318 °C (604 °F) without decomposition, and with a boiling point of 1,388 °C (2,530 °F). It is highly soluble in water, with a lower solubility in polar solvents such as ethanol and methanol.[14] NaOH is insoluble in ether and other non-polar solvents
Sodium laureth sulfate sls
Sodium laureth sulfate (SLES), an accepted contraction of sodium lauryl ether sulfate (SLES), is an anionic detergent and surfactant found in many personal care products (soaps, shampoos, toothpaste, etc.). SLES is an inexpensive and very effective foaming agent.[1] SLES, sodium lauryl sulfate (SLS), ammonium lauryl sulfate (ALS), and sodium pareth sulfate are surfactants that are used in many cosmetic products for their cleaning and emulsifying properties. It is derived from palm kernel oil or coconut oil.
Its chemical formula is CH3(CH2)11(OCH2CH2)nOSO3Na. Sometimes the number represented by n is specified in the name, for example laureth-2 sulfate. The product is heterogeneous in the number of ethoxyl groups, where n is the mean. Laureth-3 sulfate is common in commercial products.
Sodium metabisulfite
Sodium metabisulfite or sodium pyrosulfite (IUPAC spelling; Br. E. sodium metabisulphite or sodium pyrosulphite) is an inorganic compound of chemical formula Na2S2O5. The substance is sometimes referred to as disodium metabisulfite. It is used as a disinfectant, antioxidant, and preservative agent.
Preparation
Sodium disulfite can be prepared by treating a solution of sodium hydroxide with sulfur dioxide. When conducted in warm water, Na2SO3 initially precipitates as a yellow solid. With more SO2, the solid dissolves to give the disulfite, which crystallises upon cooling.
- SO2 + 2 NaOH → Na2SO3 + H2O
- SO2 + Na2SO3 → Na2S2O5
which yields a residue of colourless solid Na2S2O5.
Sodium sulfate
Sodium sulfate (also known as sodium sulphate or sulfate of soda) is the inorganic compound with formula Na2SO4 as well as several related hydrates. All forms are white solids that are highly soluble in water. With an annual production of 6 million tonnes, the decahydrate is a major commodity chemical product. It is mainly used for the manufacture of detergents and in the kraft process of paper pulping
The world production of sodium sulfate, almost exclusively in the form of the decahydrate amounts to approximately 5.5 to 6 million tonnes annually (Mt/a). In 1985, production was 4.5 Mt/a, half from natural sources, and half from chemical production. After 2000, at a stable level until 2006, natural production had increased to 4 Mt/a, and chemical production decreased to 1.5 to 2 Mt/a, with a total of 5.5 to 6 Mt/a. For all applications, naturally produced and chemically produced sodium sulfate are practically interchangeable.