Tetraammine copper nitrate

Structural formula
General
Surname	Tetraammine copper nitrate
other names	Tetrammine copper (II) nitrate Tetrammine copper dinitrate TACN
Molecular formula	[Cu (NH 3 ) 4 ] (NO 3 ) 2
External identifiers / databases
CAS number 31058-64-7 Wikidata Q21406307
properties
Molar mass	255.68 g mol −1
Physical state	firmly
safety instructions
GHS hazard labeling no classification available
As far as possible and customary, SI units are used. Unless otherwise noted, the data given apply to standard conditions .

Tetraammine copper (II) nitrate or TACN (English Tetraamminecopper (II) nitrate) is a complex salt of divalent copper and nitric acid . The deep blue color of the salt crystals is caused by the tetraammine complex [Cu (NH ₃ ) ₄ ] ²⁺ of copper, which is complexed by two additional water molecules in aqueous solution.

presentation

Tetraamminkupfer (II) nitrate is produced by adding a saturated copper (II) nitrate solution with ammonia .

${\displaystyle \mathrm {Cu(NO_{3})_{2}+4NH_{3}\rightarrow [Cu(NH_{3})_{4}](NO_{3})_{2}} }$

It can also be synthesized by dissolving copper in an ammoniacal, saturated ammonium nitrate solution , with evolution of gas, and subsequent crystallization.

${\displaystyle \mathrm {Cu+2NH_{4}NO_{3}+2NH_{3}\rightarrow [Cu(NH_{3})_{4}](NO_{3})_{2}+H_{2}} }$

Moist tetraammine copper (II) nitrate crystals

properties

Due to the strong oxidizing nitrate - anion and easily oxidized ligand ammonia this compound is unstable to heat, shock and friction. It can also act as an explosive . With a low detonation speed (2900 m / s) and low explosiveness, it is one of the weak explosives.

In the event of detonation or excessive heating, this reaction can be observed:

${\displaystyle \mathrm {[Cu(NH_{3})_{4}](NO_{3})_{2}\rightarrow Cu+3N_{2}+6H_{2}O} }$

whereby the substance first liquefies when heated up strongly, then deflagrates and the product copper still reacts with atmospheric oxygen to form copper (II) oxide .

Individual evidence

1. ↑ This substance has either not yet been classified with regard to its hazardousness or a reliable and citable source has not yet been found.
2. ↑ chem-page.de: Show experiments - tetraammine copper (II) nitrate