Difference between revisions of "Nitric acid"

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[[File:Nitric acid.png|thumb|220x220px]]
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'''Nitric acid''' is a strong acid with the formula HNO<sub>3</sub>. It is a [[mineral acid]], along with [[Hydrochloric acid|hydrochloric]], [[Sulfuric acid|sulfuric]], [[perchloric acid|perchloric]], and [[phosphoric acid]]s. It is a powerful oxidizing agent, especially when mixed with sulfuric acid, which produces the nitronium ion in situ.
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| Name = Nitric acid
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| Reference =
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| IUPACName = Nitric acid
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| PIN =
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| SystematicName = Nitric acid
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| OtherNames = Acidum nitricum<br>Aqua fortis<br>Eau forte<br>Hydrogen nitrate<br>Spirit of niter
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| Section1 = {{Chembox Identifiers
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| Section2 = {{Chembox Properties
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| AtmosphericOHRateConstant =
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| Appearance = Colorless, yellow or red [[fuming]] liquid
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| BoilingPt =
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| BoilingPtC = 83
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| BoilingPt_ref =
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| BoilingPt_notes = <br>121 °C (68%)
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| Density = 1.5129 g/cm<sup>3</sup>
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| Formula = HNO<sub>3</sub>
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| HenryConstant =
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| LogP = -0.21
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| MolarMass = 63.01 g/mol
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| MeltingPt =
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| MeltingPtC = −42
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| MeltingPt_ref =
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| MeltingPt_notes =
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| Odor = Acrid, acidic
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| pKa = -1.4
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| pKb =
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| Solubility = Miscible
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| SolubleOther =
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| Solvent =
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| VaporPressure = 48 mmHg (20 °C)
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| Section4 = {{Chembox Thermochemistry
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| DeltaGf =
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| DeltaHc =
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| DeltaHf = −207 kJ/mol
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| Entropy = 146 J·mol<sup>−1</sup>·K<sup>−1</sup>
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| HeatCapacity =
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| Section5 = {{Chembox Explosive
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| Section6 = {{Chembox Hazards
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| AutoignitionPt = Non-flammable
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| ExploLimits =
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| ExternalMSDS = [https://www.docdroid.net/tYfwyHS/nitric-acid-anhydrous-sa.pdf.html Sigma-Aldrich] (anhydrous)<br>[https://www.docdroid.net/5JipLQB/nitric-acid-65-sa.pdf.html Sigma-Aldrich] (azeotrope)
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| FlashPt = Non-flammable
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| LD50 =
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| MainHazards = Corrosive<br>Toxic
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| OtherCompounds = [[Nitrous acid]]
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'''Nitric acid''' is a strong acid with the formula '''HNO<sub>3</sub>'''. It is an important [[mineral acid]], along with [[Hydrochloric acid|hydrochloric]], [[Sulfuric acid|sulfuric]], [[perchloric acid|perchloric]], and [[phosphoric acid]]s. It is a powerful oxidizing agent, especially when mixed with sulfuric acid, which produces the nitronium ion in situ.
  
 
==Properties==
 
==Properties==
Line 6: Line 114:
 
Nitric acid is an oxidizing acid at room temperature. It is often used in the nitration of organic compounds. It is capable of dissolving metals such as [[copper]] and [[silver]] due to its oxidizing nature, and will release toxic [[nitrogen dioxide]] as an oxidation by product.
 
Nitric acid is an oxidizing acid at room temperature. It is often used in the nitration of organic compounds. It is capable of dissolving metals such as [[copper]] and [[silver]] due to its oxidizing nature, and will release toxic [[nitrogen dioxide]] as an oxidation by product.
  
−
:Cu + 8 HNO<sub>3</sub> → 3 Cu(NO<sub>3</sub>)<sub>2</sub> + 2 NO + 4 H<sub>2</sub>O
+
: Cu + 8 HNO<sub>3</sub> → 3 Cu(NO<sub>3</sub>)<sub>2</sub> + 2 NO + 4 H<sub>2</sub>O
 +
 
 +
Upon reaction with nitric acid, most metals give the corresponding nitrates. Some metalloids and metals give the oxides instead. For example, [[tin]], [[arsenic]], [[antimony]] and [[titanium]] are oxidized into tin(IV) oxide, arsenic oxide, antimony oxide, and [[titanium dioxide]] respectively. Concentrated nitric acid will form a protective layer on the surfaces of some metals, like [[iron]], [[cobalt]], [[chromium]], [[nickel]], and [[aluminium]], which prevents the metal from further reacting with the nitric acid.
 +
 
 +
Some precious metals, such as pure [[gold]] and [[platinum group metals]] do not react with nitric acid, though pure [[gold]] and [[platinum]] do react with [[aqua regia]], a mixture of concentrated nitric and [[hydrochloric acid]]s.
 +
 
 +
Concentrated nitric acid oxidizes elemental [[iodine]], [[phosphorus]] and [[sulfur]] into [[iodic acid]], [[phosphoric acid]] and [[sulfuric acid]] respectively. Although it reacts with graphite and amorphous carbon and graphite, yielding [[carbon dioxide]], it does not react with diamond. This property can be used to separate diamond from the graphite. Elemental [[boron]] resists nitric acid at standard conditions, but hot nitric acid will slowly oxidize it to [[boric acid]]. It will also not react with [[nitrogen]], [[oxygen]], [[noble gas]]es, [[silicon]] and the first three halogens ([[fluorine]], [[chlorine]], [[bromine]]).
 +
 
 +
Nitric acid is known to slowly decompose over time, a process more visible in conc. acid:
 +
 
 +
: 4 HNO<sub>3</sub> → 2 H<sub>2</sub>O + 4 NO<sub>2</sub> + O<sub>2</sub>
 +
 
 +
Nitration of organic compounds with nitric acid is the primary method of synthesis of many common explosives and other energetic materials, such as [[nitroglycerin]], [[nitrocellulose]], [[trinitrotoluene]], [[picric acid]], [[RDX]], etc. Conc. [[sulfuric acid]] is used to aid the nitration.
 +
 
 +
Nitric acid reacts with proteins to form yellow nitrated products. This reaction is known as the xanthoproteic reaction and it's used to detect the presence of proteins in a solution. The test is carried out by adding concentrated nitric acid to the substance being tested, and then heating the mixture. If proteins that contain amino acids with aromatic rings are present, the mixture turns yellow. Upon adding a base such as ammonia, the color turns orange. These color changes are caused by nitrated aromatic rings in the protein.
  
 
===Physical===
 
===Physical===
−
Concentrated nitric acid is a clear solution with a density of about 1.2 g/ml. When the concentration of the acid surpasses 70%, it becomes classified as fuming nitric acid, this can be identified by visible fuming when air is blown into it. It forms an azeotrope with water at 68% concentration, which makes it difficult to produce the pure substance.
+
Concentrated nitric acid is a clear solution with a density of about 1.2 g/ml. When the concentration of the acid surpasses 70%, it becomes classified as fuming nitric acid, this can be identified by visible fuming when air is blown into it. Nitric acid in concentrations above 90% fumes extremely profusely on any contact with air. It forms an azeotrope with water at 68% concentration, which makes it difficult to produce the pure substance.
  
 
==Availability==
 
==Availability==
 
Nitric acid is available from lab suppliers like Elemental Scientific and Duda Diesel. While the acid itself is not expensive, it requires a mandatory HAZMAT shipping fee of $37.50, making this acid rather expensive for the amateur chemist.
 
Nitric acid is available from lab suppliers like Elemental Scientific and Duda Diesel. While the acid itself is not expensive, it requires a mandatory HAZMAT shipping fee of $37.50, making this acid rather expensive for the amateur chemist.
 +
 +
Most places limit the sale of nitric acid to the general public, due to its use in the manufacturing of explosive materials. In the EU, the sale and possession of nitric acid in conc. higher than 3% (yes, THREE PERCENT) is forbidden without a license. Conc. nitric acid is also restricted to the general public in other countries.
  
 
==Preparation==
 
==Preparation==
 
[[File:IMG 0171.JPG|thumb|220x220px|Makeshift production of nitric acid by passing nitrogen dioxide gas(right) into chilled hydrogen peroxide(left).]]
 
[[File:IMG 0171.JPG|thumb|220x220px|Makeshift production of nitric acid by passing nitrogen dioxide gas(right) into chilled hydrogen peroxide(left).]]
−
Nitric acid may be prepared by distilling a mixture of a nitrate salt and one equivalent of [[sulfuric acid]] at 83ºC. This will produce 70% azeotropic concentrated acid, but the acid will be brown due to dissolved [[nitrogen dioxide]]. Dissolved nitrogen dioxide can be oxidized to nitric acid with oxygen or ozone. To produce higher concentrations with dissolved nitrogen oxides, also known as fuming nitric acid, the concentrated acid may be vacuum distilled with additional concentrated sulfuric acid. [[Hydrochloric acid]] should never be used, as it reacts with nitric acid to form [[nitrosyl chloride]].
 
  
−
If sulfuric acid of a very high concentration is used in the nitrate salt method, it is possible to distill nitric acid of higher concentration, close to 100%. However, the resulting acid will be fouled by very high concentrations of nitrogen dioxide. This product is known as ''red fuming nitric acid'', or RFNA, and appears like a red-brown liquid that releases brown fumes. RFNA can be converted to a more pure product, ''white fuming nitric acid'', by blowing oxygen through it until the disappearance of the red-brown color. White fuming nitric acid is colorless or yellow and releases white or yellow fumes. It is nitric acid with a concentration of 95 to 99%.
+
The classic method of laboratory synthesis of nitric acid is described in a sub-article:
  
−
A somewhat less efficient method of producing nitric acid is by the reaction of a mixture containing sulfuric acid and a nitrate salt with copper metal, generating large amounts of nitrogen dioxide gas. The gas may then be bubbled into [[hydrogen peroxide]] or water, with hydrogen peroxide producing a higher yield. [[Sodium bisulfate]] can also be use to replace sulfuric acid.
+
''[[Glauber's nitric acid synthesis]]''
 +
 
 +
A somewhat less efficient method of producing nitric acid is by the reaction of a mixture containing sulfuric acid and a nitrate salt with copper metal, generating large amounts of nitrogen dioxide gas. The gas may then be bubbled into [[hydrogen peroxide]] or water, with hydrogen peroxide producing a higher yield.
 +
 
 +
[[Sodium bisulfate]] can also be use to replace sulfuric acid, however the higher temperature will decompose more of the nitric acid to oxygen, nitrogen dioxide and water.
  
 
It is possible to produce nitric acid with an [[Ostwald reactor]], or by reacting [[nitrogen]] and [[oxygen]] in air with an electric spark.
 
It is possible to produce nitric acid with an [[Ostwald reactor]], or by reacting [[nitrogen]] and [[oxygen]] in air with an electric spark.
 +
 +
If you need to quickly whip up some dilute nitric acid, you can use the "quick and dirty" method, namely reacting [[calcium nitrate]] with [[sulfuric acid]]. This method has two downsides: first, even if your reagents are in a perfectly stoichiometric ratio, the resulting acid is still contaminated by a small amount of calcium sulfate that managed to stay in solution. Second, the precipitate of calcium sulfate is incredibly messy and voluminous, the acid looks like sour cream and it is almost impossible to decant it properly. Use this method only if you have a vacuum filtering set. This low-grade acid can be distilled to yield azeotropic nitric acid.
 +
 +
To get past azeotropic nitric acid and obtain red fuming nitrate acid, the azeotropic acid is distilled in the presence of a drying agent, such as solid [[magnesium nitrate]] or concentrated (>90%) sulfuric acid.
 +
 +
Yellow concentrated nitric acid can be turned white, or RFNA converted to WFNA, by bubbling oxygen though the acid. Oxygen oxidizes NO<sub>2</sub> to N<sub>2</sub>O<sub>5</sub>, which combines with the residual water in your acid to produce nearly pure nitric acid. Vacuum drying will also remove the NO2 gas.
  
 
==Projects==
 
==Projects==
 
Nitric acid can be used for many projects including make nitrate salts. When mixed with concentrated sulfuric acid or [[hydrofluoric acid]], nitric acid acts like a base and releases a nitronium ion:
 
Nitric acid can be used for many projects including make nitrate salts. When mixed with concentrated sulfuric acid or [[hydrofluoric acid]], nitric acid acts like a base and releases a nitronium ion:
  
−
:2H<sub>2</sub>SO<sub>4</sub> + HNO<sub>3</sub> → NO<sub>2</sub><sup>+</sup> + 2HSO<sub>4</sub><sup>-</sup> + H<sub>2</sub>O
+
:2 H<sub>2</sub>SO<sub>4</sub> + HNO<sub>3</sub> → NO<sub>2</sub><sup>+</sup> + 2 HSO<sub>4</sub><sup>-</sup> + H<sub>2</sub>O
  
−
This mixture, known as [[mixed acid]] can be used for nitrating many organic compounds.
+
This mixture, known as [[nitrating mixture]] or mixed acid can be used for nitrating many organic compounds.
  
 
Other:
 
Other:
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*Make [[aqua regia]]
 
*Make [[aqua regia]]
 
*Purify [[silver]]
 
*Purify [[silver]]
 +
*Make nitrated explosive compounds
 +
*Artificially age wood (pine and maple)
 +
*Make nital (etchant)
 +
*Pickling [[stainless steel]]
  
 
==Handling==
 
==Handling==
 
===Safety===
 
===Safety===
 
Nitric acid solutions are highly corrosive and will stain the skin yellow as the proteins are nitrated. Care should be taken to not let nitric acid contact the skin. Nitrates should not be used with hydrochloric acid, because this generates nitrosyl chloride.
 
Nitric acid solutions are highly corrosive and will stain the skin yellow as the proteins are nitrated. Care should be taken to not let nitric acid contact the skin. Nitrates should not be used with hydrochloric acid, because this generates nitrosyl chloride.
 +
 +
Most glove types (with the notable exceptions butyl rubber or neoprene) are incompatible due to the strong oxidizing effects of nitric acid and may burn upon contact with the acid.<ref>http://www.ansellpro.com/download/Ansell_7thEditionChemicalResistanceGuide.pdf</ref> When handling fuming nitric acid, wear butyl rubber gloves. Other types of rubber may react extremely violently with nitric acid of this concentration. If you don't have butyl rubber, don't wear gloves at all: damage done to your bare hands will be lesser than what rubber on fire can do to you. Nitric acid in general reacts with rubber; do not try to distill it in apparata that contain rubber parts. Use ground glass joints or a retort when distilling nitric acid, especially of fuming concentration.
  
 
===Storage===
 
===Storage===
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===Disposal===
 
===Disposal===
−
Nitric acid can be neutralized with neutralizing compounds, such as carbonates, bicarbonates, oxides, hydroxides. Calcium carbonate is a good neutralizing agent, and, as long as the acid isn't contaminated with heavy metals, the resulting calcium nitrate can be discarded in ground or poured down the drain.
+
Nitric acid can be neutralized with neutralizing compounds, such as carbonates, bicarbonates, oxides, hydroxides. Calcium carbonate is a good neutralizing agent, and, as long as the acid isn't contaminated with heavy metals, the resulting calcium nitrate can be discarded in ground or poured down the drain. Concentrated nitric acid (>50%) must first be diluted in cold water, before being neutralized with a base, to limit the amount of corrosive fumes/aerosols released in air during the neutralization process.
  
 
==References==
 
==References==
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===Relevant Sciencemadness threads===
 
===Relevant Sciencemadness threads===
 
*[http://www.sciencemadness.org/talk/viewthread.php?tid=27851 Nitric acid and silver nitrate]
 
*[http://www.sciencemadness.org/talk/viewthread.php?tid=27851 Nitric acid and silver nitrate]
−
[[Category:Strong acids]]
+
*[http://www.sciencemadness.org/talk/viewthread.php?tid=13749 help make white fuming nitric acid.]
−
[[Category:Acids]]
+
*[http://www.sciencemadness.org/talk/viewthread.php?tid=155352 My problem with pure fuming hno3]
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[[Category:Inorganic compounds]]
+
*[http://www.sciencemadness.org/talk/viewthread.php?tid=157364 RFNA and Vacuum Distillation of H2SO4]
−
[[Category:Oxidizing agents]]
+
 
−
[[Category:Nitrates]]
+
 
[[Category:Chemical compounds]]
 
[[Category:Chemical compounds]]
−
[[Category:Things that can kill you very quickly]]
+
[[Category:Inorganic compounds]]
 +
[[Category:Acids]]
 +
[[Category:Strong acids]]
 
[[Category:Mineral acids]]
 
[[Category:Mineral acids]]
 +
[[Category:Oxoacids]]
 +
[[Category:Nitrates]]
 +
[[Category:Oxidizing agents]]
 
[[Category:Materials unstable in basic solution]]
 
[[Category:Materials unstable in basic solution]]
 +
[[Category:Things that can kill you very quickly]]
 +
[[Category:Essential reagents]]
 
[[Category:Corrosive chemicals]]
 
[[Category:Corrosive chemicals]]
 +
[[Category:Irritants]]
 +
[[Category:Liquids]]

Latest revision as of 11:53, 23 September 2023

Nitric acid
Nitric acid.png
Names
IUPAC name
Nitric acid
Systematic IUPAC name
Nitric acid
Other names
Acidum nitricum
Aqua fortis
Eau forte
Hydrogen nitrate
Spirit of niter
Properties
HNO3
Molar mass 63.01 g/mol
Appearance Colorless, yellow or red fuming liquid
Odor Acrid, acidic
Density 1.5129 g/cm3
Melting point −42 °C (−44 °F; 231 K)
Boiling point 83 °C (181 °F; 356 K)
121 °C (68%)
Miscible
Vapor pressure 48 mmHg (20 °C)
Acidity (pKa) -1.4
Thermochemistry
146 J·mol−1·K−1
−207 kJ/mol
Hazards
Safety data sheet Sigma-Aldrich (anhydrous)
Sigma-Aldrich (azeotrope)
Flash point Non-flammable
Related compounds
Related compounds
 Nitrous acid
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
Infobox references

Nitric acid is a strong acid with the formula HNO3. It is an important mineral acid, along with hydrochloric, sulfuric, perchloric, and phosphoric acids. It is a powerful oxidizing agent, especially when mixed with sulfuric acid, which produces the nitronium ion in situ.

Properties

Chemical

Nitric acid is an oxidizing acid at room temperature. It is often used in the nitration of organic compounds. It is capable of dissolving metals such as copper and silver due to its oxidizing nature, and will release toxic nitrogen dioxide as an oxidation by product.

Cu + 8 HNO3 → 3 Cu(NO3)2 + 2 NO + 4 H2O

Upon reaction with nitric acid, most metals give the corresponding nitrates. Some metalloids and metals give the oxides instead. For example, tin, arsenic, antimony and titanium are oxidized into tin(IV) oxide, arsenic oxide, antimony oxide, and titanium dioxide respectively. Concentrated nitric acid will form a protective layer on the surfaces of some metals, like iron, cobalt, chromium, nickel, and aluminium, which prevents the metal from further reacting with the nitric acid.

Some precious metals, such as pure gold and platinum group metals do not react with nitric acid, though pure gold and platinum do react with aqua regia, a mixture of concentrated nitric and hydrochloric acids.

Concentrated nitric acid oxidizes elemental iodine, phosphorus and sulfur into iodic acid, phosphoric acid and sulfuric acid respectively. Although it reacts with graphite and amorphous carbon and graphite, yielding carbon dioxide, it does not react with diamond. This property can be used to separate diamond from the graphite. Elemental boron resists nitric acid at standard conditions, but hot nitric acid will slowly oxidize it to boric acid. It will also not react with nitrogen, oxygen, noble gases, silicon and the first three halogens (fluorine, chlorine, bromine).

Nitric acid is known to slowly decompose over time, a process more visible in conc. acid:

4 HNO3 → 2 H2O + 4 NO2 + O2

Nitration of organic compounds with nitric acid is the primary method of synthesis of many common explosives and other energetic materials, such as nitroglycerin, nitrocellulose, trinitrotoluene, picric acid, RDX, etc. Conc. sulfuric acid is used to aid the nitration.

Nitric acid reacts with proteins to form yellow nitrated products. This reaction is known as the xanthoproteic reaction and it's used to detect the presence of proteins in a solution. The test is carried out by adding concentrated nitric acid to the substance being tested, and then heating the mixture. If proteins that contain amino acids with aromatic rings are present, the mixture turns yellow. Upon adding a base such as ammonia, the color turns orange. These color changes are caused by nitrated aromatic rings in the protein.

Physical

Concentrated nitric acid is a clear solution with a density of about 1.2 g/ml. When the concentration of the acid surpasses 70%, it becomes classified as fuming nitric acid, this can be identified by visible fuming when air is blown into it. Nitric acid in concentrations above 90% fumes extremely profusely on any contact with air. It forms an azeotrope with water at 68% concentration, which makes it difficult to produce the pure substance.

Availability

Nitric acid is available from lab suppliers like Elemental Scientific and Duda Diesel. While the acid itself is not expensive, it requires a mandatory HAZMAT shipping fee of $37.50, making this acid rather expensive for the amateur chemist.

Most places limit the sale of nitric acid to the general public, due to its use in the manufacturing of explosive materials. In the EU, the sale and possession of nitric acid in conc. higher than 3% (yes, THREE PERCENT) is forbidden without a license. Conc. nitric acid is also restricted to the general public in other countries.

Preparation

Makeshift production of nitric acid by passing nitrogen dioxide gas(right) into chilled hydrogen peroxide(left).

The classic method of laboratory synthesis of nitric acid is described in a sub-article:

Glauber's nitric acid synthesis

A somewhat less efficient method of producing nitric acid is by the reaction of a mixture containing sulfuric acid and a nitrate salt with copper metal, generating large amounts of nitrogen dioxide gas. The gas may then be bubbled into hydrogen peroxide or water, with hydrogen peroxide producing a higher yield.

Sodium bisulfate can also be use to replace sulfuric acid, however the higher temperature will decompose more of the nitric acid to oxygen, nitrogen dioxide and water.

It is possible to produce nitric acid with an Ostwald reactor, or by reacting nitrogen and oxygen in air with an electric spark.

If you need to quickly whip up some dilute nitric acid, you can use the "quick and dirty" method, namely reacting calcium nitrate with sulfuric acid. This method has two downsides: first, even if your reagents are in a perfectly stoichiometric ratio, the resulting acid is still contaminated by a small amount of calcium sulfate that managed to stay in solution. Second, the precipitate of calcium sulfate is incredibly messy and voluminous, the acid looks like sour cream and it is almost impossible to decant it properly. Use this method only if you have a vacuum filtering set. This low-grade acid can be distilled to yield azeotropic nitric acid.

To get past azeotropic nitric acid and obtain red fuming nitrate acid, the azeotropic acid is distilled in the presence of a drying agent, such as solid magnesium nitrate or concentrated (>90%) sulfuric acid.

Yellow concentrated nitric acid can be turned white, or RFNA converted to WFNA, by bubbling oxygen though the acid. Oxygen oxidizes NO2 to N2O5, which combines with the residual water in your acid to produce nearly pure nitric acid. Vacuum drying will also remove the NO2 gas.

Projects

Nitric acid can be used for many projects including make nitrate salts. When mixed with concentrated sulfuric acid or hydrofluoric acid, nitric acid acts like a base and releases a nitronium ion:

2 H2SO4 + HNO3 → NO2+ + 2 HSO4- + H2O

This mixture, known as nitrating mixture or mixed acid can be used for nitrating many organic compounds.

Other:

Handling

Safety

Nitric acid solutions are highly corrosive and will stain the skin yellow as the proteins are nitrated. Care should be taken to not let nitric acid contact the skin. Nitrates should not be used with hydrochloric acid, because this generates nitrosyl chloride.

Most glove types (with the notable exceptions butyl rubber or neoprene) are incompatible due to the strong oxidizing effects of nitric acid and may burn upon contact with the acid.[1] When handling fuming nitric acid, wear butyl rubber gloves. Other types of rubber may react extremely violently with nitric acid of this concentration. If you don't have butyl rubber, don't wear gloves at all: damage done to your bare hands will be lesser than what rubber on fire can do to you. Nitric acid in general reacts with rubber; do not try to distill it in apparata that contain rubber parts. Use ground glass joints or a retort when distilling nitric acid, especially of fuming concentration.

Storage

Nitric acid is incompatible with most plastics due to its oxidizing nature, though bottle lids made of polypropylene (PP) are acceptable. High concentrations of nitric acid are light sensitive and should be kept in amber glass bottles with ample headroom to prevent pressure build up from nitrogen oxides.

Disposal

Nitric acid can be neutralized with neutralizing compounds, such as carbonates, bicarbonates, oxides, hydroxides. Calcium carbonate is a good neutralizing agent, and, as long as the acid isn't contaminated with heavy metals, the resulting calcium nitrate can be discarded in ground or poured down the drain. Concentrated nitric acid (>50%) must first be diluted in cold water, before being neutralized with a base, to limit the amount of corrosive fumes/aerosols released in air during the neutralization process.

References

  1. ↑ http://www.ansellpro.com/download/Ansell_7thEditionChemicalResistanceGuide.pdf

Relevant Sciencemadness threads

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