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Potassium permanganate

Potassium permanganate is an inorganic compound with the chemical formula KMnO4 and composed of K+ and MnO 4. It is a purplish-black crystalline solid, that dissolves in water to give intensely pink or purple solutions

Sanitary paraffin 175 kg barrel

Paraffin wax is mostly found as a white, odorless, tasteless, waxy solid, with a typical melting point between about 46 and 68 °C (115 and 154 °F), and a density of around 900 kg/m3. It is insoluble in water, but soluble in ether, benzene, and certain esters. Paraffin is unaffected by most common chemical reagents but burns readily. Its heat of combustion is 42 MJ/kg.

The hydrocarbon C31H64 is a typical component of paraffin wax.

Paraffin wax is an excellent electrical insulator, with a resistivity of between 1013 and 1017 ohm metre. This is better than nearly all other materials except some plastics (notably Teflon). It is an effective neutron moderator and was used in James Chadwick's 1932 experiments to identify the neutron.

Paraffin wax is an excellent material for storing heat, with a specific heat capacity of 2.14–2.9 J g−1 K−1 (joules per gram kelvin) and a heat of fusion of 200–220 J g−1. Paraffin wax phase-change cooling coupled with retractable radiators was used to cool the electronics of the Lunar Roving Vehicle during the manned missions to the Moon in the early 1970s.Wax expands considerably when it melts and this allows its use in wax element thermostats for industrial, domestic and, particularly, automobile purposes.

Sodium bicarbonate 

Sodium bicarbonate (IUPAC name: sodium hydrogen carbonate), commonly known as baking soda (especially in North America and New Zealand) or bicarbonate of soda, is a chemical compound with the formula NaHCO3. It is a salt composed of a sodium cation (Na+) and a bicarbonate anion (HCO3). 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

Sodium carbonate (Semnan)

Sodium carbonate, Na2CO3, (also known as washing sodasoda ash and soda crystals) is the inorganic compound with the formula Na2CO3 and its various hydrates. All forms are white, water-soluble salts. All forms have a strongly alkaline taste and give moderately alkaline solutions in water. Historically it was extracted from the ashes of plants growing in sodium-rich soils. Because the ashes of these sodium-rich plants were noticeably different from ashes of wood (once used to produce potash), sodium carbonate became known as "soda ash."  It is produced in large quantities from sodium chloride and limestone by the Solvay process.

Main applications

In terms of its largest applications, sodium carbonate is used in the manufacture of glass, paper, rayon, soaps, and detergents.

Sodium carbonate (Turkey)

Sodium carbonate, Na2CO3, (also known as washing sodasoda ash and soda crystals) is the inorganic compound with the formula Na2CO3 and its various hydrates. All forms are white, water-soluble salts. All forms have a strongly alkaline taste and give moderately alkaline solutions in water. Historically it was extracted from the ashes of plants growing in sodium-rich soils. Because the ashes of these sodium-rich plants were noticeably different from ashes of wood (once used to produce potash), sodium carbonate became known as "soda ash."  It is produced in large quantities from sodium chloride and limestone by the Solvay process.

Main applications

In terms of its largest applications, sodium carbonate is used in the manufacture of glass, paper, rayon, soaps, and detergents.

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

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 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.