Difference between revisions of "Nitrating mixture"

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'''Nitrating mixture''' is the name given to the mixture of concentrated [[nitric acid]] and [[sulfuric acid]], in a 1:1 ratio, used in the [[nitration]] of organic substances. The sulfuric acid in this mixture is sufficiently strong to protonate nitric acid, producing the [[nitronium]] ion (NO<sub>2</sub><sup>+</sup>), which is the active species in aromatic nitration.<ref>http://en.wikipedia.org/wiki/Nitration</ref>
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'''Nitrating mixture''' is the name given to the mixture of concentrated [[nitric acid]] and [[sulfuric acid]], in a 1:1 ratio, used in the [[nitration]] of organic substances. The sulfuric acid in this mixture is sufficiently strong to protonate nitric acid, producing the [[nitronium]] ion (NO<sub>2</sub><sup>+</sup>), which is the active species in aromatic nitration.<ref>http://en.wikipedia.org/wiki/Nitration</ref> It is also sometimes referred to as '''mixed acid'''.
  
 
==Properties==
 
==Properties==
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===Relevant Sciencemadness threads===
 
===Relevant Sciencemadness threads===
 
*[http://www.sciencemadness.org/talk/viewthread.php?tid=21611 Nitric / sulfuric acid mixture question]
 
*[http://www.sciencemadness.org/talk/viewthread.php?tid=21611 Nitric / sulfuric acid mixture question]
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[[Category:Oxidizing mixtures]]
 
[[Category:Oxidizing mixtures]]
 
[[Category:Acids]]
 
[[Category:Acids]]

Revision as of 20:06, 10 October 2015

Nitrating mixture is the name given to the mixture of concentrated nitric acid and sulfuric acid, in a 1:1 ratio, used in the nitration of organic substances. The sulfuric acid in this mixture is sufficiently strong to protonate nitric acid, producing the nitronium ion (NO2+), which is the active species in aromatic nitration.[1] It is also sometimes referred to as mixed acid.

Properties

Nitrating acid is a colorless to yellow-reddish liquid, sometimes fuming reddish brown vapors (nitrogen dioxide). It is miscible with water and the dissolution releases large amounts of heat. [2]

The mixed acid solution is used in the preparation of aromatic nitrates, such as nitrobenzene, TNP, TNT, etc.

Mixed acid reacts vigorously with organic substances, generating heat and nitrogen dioxide gas.

Preparation

Nitrating mixture is prepared by cooling a volume of concentrated sulfuric acid, usually on an ice bath. An equal volume of concentrated nitric acid is slowly added, keeping the solution at constant temperature. A cheaper nitrating mixture may be made by adding potassium nitrate to sulfuric acid though it may not work for some reactions.

Safety

Mixed acid is highly corrosive and is a fire hazard. It is unstable, and should be generated in situ.

References

  1. http://en.wikipedia.org/wiki/Nitration
  2. http://cameochemicals.noaa.gov/chemical/7195

Relevant Sciencemadness threads