Borax , also known as sodium borate , sodium tetraborate , or disodium tetraborate , is an important boron compound, a mineral , and boric acid salt. Borax powder is white, consisting of a soft colorless crystal that dissolves in water. A number of different closely related minerals or chemical compounds in their water crystals are referred to as borax , but the word is usually used to refer to decahydrate. Borax is sold commercially partially dehydrated.
Borax is a component of many detergents, cosmetics, and enamel glazes. It is used to make a buffer solution in biochemistry, as a fire retardant, as an anti-fungal compound, in the manufacture of fiberglass, as flux in metallurgy, a neutron capture shield for radioactive sources, a texturing agent in cooking, as a precursor for other boron compounds, with boric acid, useful as an insecticide.
In artisanal gold mining, the borax method is sometimes used instead of toxic mercury in the gold extraction process. Borax was reportedly used by gold miners in several parts of the Philippines in the 1900s.
Borax was first discovered in a dry lake bed in Tibet and imported through the Silk Road to the Arabian Peninsula in the 8th century. Borax first began to be used in the late 19th century when Pacific Coast Ship Corporation Francis Marion Smith began marketing and popularizing a wide range of applications under the Borax Mule Team's 20 brands, named by the method that was originally borrowed out of California and Nevada deserts in quantities big enough to make it cheap and available in general.
Video Borax
Chemistry
The term
Borax is generally described as Na 2 B 4 O 7 Ã, Â · 10H 2 O. However, this is more well formulated as Na 2 Sub <5 (OH) 4 ] Ã, Â · 8H 2 O, because borax contains 4 <2> > ion. In this structure, there are two boron atoms four coordinates (two BO 4 tetrahedra) and two boron atoms three coordinates (two BO triangles 3 ).
Borax is also easily converted into boric acid and other borates, which have many applications. The reaction with hydrochloric acid to form boric acid is:
- Na 2 B 4 O 7 Ã, Â · 10H 2 O 2 HCl - > 4 H 3 BO 3 2 NaCl 5 H 2 O
The "decahydrate" is stable enough to find use as the main standard for acid-base titrimetry.
When borax is added to the flame, it produces a yellow green color. Borax is not used for this purpose in fireworks due to the extraordinary yellow color of sodium. Boric acid is used for transparent green methanol fire colors.
Maps Borax
Etymology
The English word
The word "tinkle", or tinched "tinker", refers to raw borax, before it is purified, as it is mined from lake deposits in Tibet, Persia, and other parts of Asia. This word was adopted in the 17th century from Malay tingkal and from Urdu/Persian/Arabic ????? ? tink? r/tank? r ; two forms are in English. These all seem to be related to Sanskrit ????? ?? nka? a .
Natural resources
Borax occurs naturally in the evaporite deposits produced by repeated seasonal lake evaporation. The most important commercial deposits are found in: Turkey; Boron, California; and Searles Lake, California. Also, borax has been found in many other locations in the Southwest of the United States, the Atacama desert in Chile, new deposits found in Bolivia, and in Tibet and Romania. Borax can also be produced synthetically from other boron compounds.
Natural Borax (known by the trade name Rasorite-46 in the United States and many other countries) is perfected by the recrystallization process.
Usage
Household products
Borax is used in many household laundry and cleaning products, including "20 Mule Team Borax" washing machines, hand-soap "Boraxo" hand towels, and some teeth whitening formulas.
buffer pH
Boron ions (commonly supplied as boric acid) are used in biochemical and chemical laboratories to make buffers, for example for polyacrylamide gel electrophoresis DNA and RNA, such as TBE buffers (buffered tris-hydroxymethylaminomethonium buffers) or buffer buffer buffer or new BBS (borate buffered saline) in the coating procedure. Borate buffers (usually at pH 8) are also used as preferential equilibration solutions in crosslinking reaction dimethyl pimelimidate (DMP).
Agent co-complexing
Borax as a borate source has been used to take advantage of the ability of co-complexing borates with other agents in water to form complex ions with various substances. Borate and suitable polymer beds are used for non-glycosylated hemoglobin chromatography different from glycosylated hemoglobin (especially HbA1c), which is an indicator of long-term hyperglycemia in diabetes mellitus.
Water softening agent
Borax itself has no high affinity for violent cations, although it has been used for water softening. The chemical equation for water softening is given below:
- Ca 2 (aq) Na 2 B 4 O 7 (aq ) -> CaB 4 O 7 (s) ? 2 Na (aq) sub> -> MgB 4 O 7 (s) ? 2 Na (aq)
The introduced sodium ion does not make the water 'hard'. This method is suitable for eliminating types of temporary and permanent violence.
Flux
The mixture of borax and ammonium chloride is used as flux when welding iron and steel. This lowers the melting point of the unwanted iron oxide (scale), allowing it to run. Borax is also used mixed with water as a flux when soldering metal jewelry such as gold or silver, where it allows the liquid solder to wet the metal and flows evenly into the joint. Borax is also a good flux for "pre-tinning" tungsten with zinc - making it tungsten-solderable. Borax is often used as a flux for forging welding.
Small scale gold mining
Borax replaces mercury as the preferred method for extracting gold at small-scale mining facilities. This method is called borax method and is used in the Philippines.
Flubber
Rubber polymers are sometimes called Slime, Flubber, 'gluep' or 'glurch' (or incorrectly called Silly Putty, based on silicon polymers), can be made with crosslinked polyvinyl alcohol with borax. Creating flubber from polyvinyl acetate based glue, such as Elmer's Glue, and borax are common basic-science demonstrations.
Food additives
Borax, numbered E E285 , is used as food additives in some countries, but is banned in some countries, such as the US, and Thailand. As a result, certain foods, such as caviar, produced for sale in the US contain higher levels of salt to help with preservation. Its use as a cooking ingredient is to add a hard rubbery texture to the food, or as a preservative. In oriental cuisine is mostly used for texturing properties. In Asia, borax (Chinese: ?? ; pinyin: pÃÆ' Â © ng sh? or Chinese: ?? ; pinyin: yuÃÆ'¨ shÃÆ' ) is found to have been added to some Chinese food such as handmade noodles and some rice noodles like shahe fen, kway teow and chee cheong recipes are fun. In Indonesia it is a common additive, but forbidden, for food such as noodles, meatballs (meatballs), and steamed rice. The Consumer Protection Directorates in the country warned of the risk of liver cancer with high consumption over a 5-10 year period.
Other uses
- Material in enamel glaze
- Glass, pottery, and ceramic components
- Used as an additive in ceramic and glaze slip to improve suitability on wet, green equipment, and bisque
- Flame retard
- Anti-fungal compounds for cellulose isolation
- Moth proofing 10% solution for wool
- Crushed for stubborn pest prevention (eg German cockroaches) in cabinets, plumbing and cables, wall panel gaps, and unreachable locations where ordinary pesticides are undesirable
- Anti-fungus soak feet
- Precursors for sodium perborate monohydrate used in detergents, as well as for boric acid and other borates
- Packaging materials in casein, starch, and dextrin glue
- Precursors for boric acid, tackifier materials in polyvinyl acetate, polyvinyl alcohol based adhesives
- Fluoride detoxification
- Treatment for canker sores on hoofs
- To create an indelible ink for a dye by dissolving shellac onto a heated borax
- Preservative for snake skin
- Preservatives for salmon eggs, for use in sports for salmon fishing
- Pool buffer agent to control pH
- Neutron absorber, used in nuclear reactors and depleting fuel sources to control reactivity and to kill nuclear chain reactions
- As a micronutrient fertilizer to repair the boron-deficient soil.
- Preservatives in taxidermy
- To clean the skull brain cavity to be installed
- To color a fire in green
- Traditionally used to coat dried meats such as hams to protect them from becoming flies when stored further
- Found in some commercial vitamin supplements
- To stop the car radiator and engine block leak
- Used by a blacksmith in forging welding
- Used as a woodworm treatment (diluted in water)
- Used in the care or prevention of wood decay on classic wooden boats
- Used to enrich bits with Boron when leaves wither
Toxicity
Borax, sodium tetraborate decahydrate, according to one study, is not very toxic. LD 50 (median lethal dose) score was tested at 2.66 g/kg in mice, meaning that significant chemical doses were required to cause severe symptoms or death. Deadly doses do not have to be the same for humans. On the website information pesticides are listed as non-lethal compounds and no harmful issues.
Borax has been used as an insecticide in the United States with various restrictions since 1946. All restrictions were removed in February 1986 due to low borax toxicity, as reported in two EPA documents related to boric acid and borax.
- EPA has determined that, because they have low toxicity and naturally occurring, boric acid and sodium salt must be exempt from the tolerance requirements (residual maximum limit) for all crude agricultural commodities.
Although cited data were not conclusive, a re-evaluation in 2006 by the EPA still found that "no signs of toxicity were observed during the study and no evidence of cytotoxicity of target organs." In re-evaluation, a toxicity study due to overexposure is examined and the finding is that "The risk of handling residential inhalers due to boric acid and its sodium salt as an active ingredient is not a risk and does not exceed the level of concern." But that may be the risk of irritation in children inhale it if used as a powder to clean the carpet.
Sodium tetraborate decahydrate does not have known hazard problems.
Conditions defined as "excessive exposure" to borax dust may cause respiratory irritation, while no skin irritation is known to exist due to borax. Ingestion can cause indigestion including nausea, persistent vomiting, abdominal pain, and diarrhea. Effects on the vascular system and the human brain include headaches and lethargy, but more rarely. "In severe poisoning, a severe red skin rash affecting the palms, soles of the feet, buttocks and scrotum has been described, with severe poisoning, erythematous and exfoliative rashes, unconsciousness, respiratory depression, and renal failure."
A risk assessment design released by Health Canada in July 2016 has found that excessive exposure to boric acid has the potential to cause developmental and reproductive health effects. Because people are already exposed to boric acid naturally through their food and water, Health Canada suggests that exposure from other sources should be reduced as much as possible, especially for children and pregnant women. The problem is not with one product, but more than a few exposures from various sources. With this in mind, the department also announced that registration for certain pesticides containing boric acid, commonly used at home, would cancel its registration and be removed from the market. In addition, a more protective new label direction is being introduced for other boric acidic pesticides that continue to be registered in Canada (eg, closed feed stations and spot treatments using gel formulations).
Possibility of carcinogen
The Indonesian Directorate of Consumer Protection warns of liver cancer risk with high borax consumption over a 5-10 year period.
Risk of fertility and pregnancy
Borax was added to the list of candidates for Highly Concerned Substance (SVHC) on December 16, 2010. The SVHC candidate list is part of the EU Regulations on Registration, Evaluation, Authorization and Restriction of Chemicals 2006 (REACH), and the additions are based on the revised borax classification as a category toxic for reproduction 1B under CLP Rules. The imported substances and mixtures to the EU containing borax should now be labeled warning "May damage fertility" and "May damage the unborn fetus". Proposed in addition to ACHIEVING Annex XIV by ECHA on July 1, 2015. If this recommendation is approved, all import and use of borax in the EU must be authorized by ECHA. Overview of boron toxicity (such as boric acid and borate) published in 2012 in the Journal of Toxicology and Environmental Health concluded: "This clearly shows that human B [boron] exposure, even in the highest exposed cohort, is too low to reach blood (and target tissue) concentrations that will be needed to exert adverse effects on the reproductive function. "
See also
References
External links
- International Chemical Safety Card 0567
- International Chemical Safety Card 1229 (fused borax)
- Inventory of National Pollutants - Boron and compounds
- The NIOSH Pocket Guide for Chemical Hazards
- Sodium Borate at sefsc.noaa.gov
Source of the article : Wikipedia
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