Difference between revisions of "Tetrachlorocupric acid"

From Sciencemadness Wiki
Jump to: navigation, search
 
(8 intermediate revisions by the same user not shown)
Line 1: Line 1:
 
{{Stub}}
 
{{Stub}}
−
 
+
{{Chembox
−
[[File:IMGP0020.jpg|thumb|280px|Tetrachlorocupric acid formed from copper metal, hydrochloric acid, and hydrogen peroxide as an intermediate in the synthesis of copper(II) chloride]]
+
| Name = Tetrachlorocupric acid
−
 
+
| Reference =
−
'''Tetrachlorocupric acid '''is an [[Acid|acid]] formed from the [[tetrachlorocuprate]] ion. It is not stable as a solid, rather converting back to [[hydrochloric acid|h]][[hydrochloric acid|ydrochloric acid]] and [[copper(II) chloride]]. However, it is an extremely useful [[Printed circuit board etchant|printed circuit board (PCB) etchant]].
+
| IUPACName =
 +
| PIN =
 +
| SystematicName =
 +
| OtherNames =
 +
<!-- Images -->
 +
| ImageFile = Tetrachlorocupric acid with copper by Zts16.jpg
 +
| ImageSize = 280
 +
| ImageAlt =
 +
| ImageName =
 +
| ImageCaption = Tetrachlorocupric acid formed from copper metal, hydrochloric acid, and hydrogen peroxide as an intermediate in the synthesis of copper(II) chloride
 +
| ImageFile1 =
 +
| ImageSize1 =
 +
| ImageAlt1 =
 +
| ImageName1 =
 +
| ImageFile2 =
 +
| ImageSize2 =
 +
| ImageAlt2 =
 +
| ImageName2 =
 +
| ImageFile3 =
 +
| ImageSize3 =
 +
| ImageAlt3 =
 +
| ImageName3 =
 +
| ImageFileL1 =
 +
| ImageSizeL1 =
 +
| ImageAltL1 =
 +
| ImageNameL1 =
 +
| ImageFileR1 =
 +
| ImageSizeR1 =
 +
| ImageAltR1 =
 +
| ImageNameR1 =
 +
| ImageFileL2 =
 +
| ImageSizeL2 =
 +
| ImageAltL2 =
 +
| ImageNameL2 =
 +
| ImageFileR2 =
 +
| ImageSizeR2 =
 +
| ImageAltR2 =
 +
| ImageNameR2 =
 +
<!-- Sections -->
 +
| Section1 = {{Chembox Identifiers
 +
| 3DMet =
 +
| Abbreviations =
 +
| SMILES =
 +
  }}
 +
| Section2 = {{Chembox Properties
 +
| AtmosphericOHRateConstant =
 +
| Appearance = Green liquid (solution)
 +
| BoilingPt =
 +
| BoilingPtC =
 +
| BoilingPt_ref =
 +
| BoilingPt_notes = Decomposes
 +
| Density =
 +
| Formula = H<sub>2</sub>CuCl<sub>4</sub>
 +
| HenryConstant =
 +
| LogP =
 +
| MolarMass = 207.37 g/mol
 +
| MeltingPt =
 +
| MeltingPtC =
 +
| MeltingPt_ref =
 +
| MeltingPt_notes = Decomposes
 +
| pKa =
 +
| pKb =
 +
| Solubility = Perfectly soluble, stable in acidic water
 +
| SolubleOther = Insoluble in organic solvents, decomposes
 +
| Solvent =
 +
| VaporPressure =
 +
  }}
 +
| Section3 = {{Chembox Structure
 +
| Coordination =
 +
| CrystalStruct =
 +
| MolShape =
 +
  }}
 +
| Section4 = {{Chembox Thermochemistry
 +
| DeltaGf =
 +
| DeltaHc =
 +
| DeltaHf =
 +
| Entropy =
 +
| HeatCapacity =
 +
  }}
 +
| Section5 = {{Chembox Explosive
 +
| ShockSens =
 +
| FrictionSens =
 +
| DetonationV =
 +
| REFactor =
 +
  }}
 +
| Section6 = {{Chembox Hazards
 +
| AutoignitionPt = Non-flammable
 +
| ExploLimits = Non-explosive
 +
| ExternalMSDS = None
 +
| FlashPt = Non-flammable
 +
| LD50 =
 +
| LC50 =
 +
| MainHazards = Corrosive
 +
| NFPA-F =
 +
| NFPA-H =
 +
| NFPA-R =
 +
| NFPA-S =
 +
  }}
 +
| Section7 = {{Chembox Related
 +
| OtherAnions =
 +
| OtherCations =
 +
| OtherFunction =
 +
| OtherFunction_label =
 +
| OtherCompounds = [[Hydrochloric acid]]<br>[[Copper(II) chloride]]
 +
  }}
 +
}}
 +
'''Tetrachlorocupric acid '''is an [[Acid|acid]] formed from the [[tetrachlorocuprate]] ion. It is not stable as a solid, rather converting back to [[hydrochloric acid]] and [[copper(II) chloride]]. However, it is an extremely useful printed circuit board (PCB) etchant.
  
 
==Properties==
 
==Properties==
−
Tetrachlorocupric acid exists as a green solution due to the presence of [[tetrachlorocuprate]] ions. It is stable, but may emit some hydrogen chloride, so it should be stored in a capped container to prevent degradation.
+
===Chemical===
−
 
+
 
When exposed to copper, the tetrachlorocuprate ion comproportionates with the copper metal to form the dichlorocuprate(I) ion:
 
When exposed to copper, the tetrachlorocuprate ion comproportionates with the copper metal to form the dichlorocuprate(I) ion:
  
−
CuCl<sub>4</sub><sup>2-</sup> + Cu → 2CuCl<sub>2</sub><sup>-</sup>
+
: CuCl<sub>4</sub><sup>2-</sup> + Cu → 2 CuCl<sub>2</sub><sup>-</sup>
  
 
For simple etching, the presence of tetrachlorocuprate is enough to do the job. However, the acidity of tetrachlorocupric acid has the added bonus of allowing the solution to regenerate and be reused when exposed to air:
 
For simple etching, the presence of tetrachlorocuprate is enough to do the job. However, the acidity of tetrachlorocupric acid has the added bonus of allowing the solution to regenerate and be reused when exposed to air:
  
−
4H<sup>+</sup> + 8Cl<sup>-</sup> + 4CuCl<sub>2</sub><sup>-</sup> + O<sub>2</sub> → 4CuCl<sub>4</sub><sup>2-</sup> + 2H<sub>2</sub>O
+
: 4 H<sup>+</sup> + 8 Cl<sup>-</sup> + 4 CuCl<sub>2</sub><sup>-</sup> + O<sub>2</sub> → 4 CuCl<sub>4</sub><sup>2-</sup> + 2 H<sub>2</sub>O
  
 
This reaction can be accelerated by adding hydrogen peroxide.
 
This reaction can be accelerated by adding hydrogen peroxide.
  
 
Tetrachlorocuprates are able to dissolve many other metals, notably aluminum.
 
Tetrachlorocuprates are able to dissolve many other metals, notably aluminum.
 +
 +
===Physical===
 +
Tetrachlorocupric acid exists as a green solution due to the presence of [[tetrachlorocuprate]] ions. It is stable, but may emit some hydrogen chloride, so it should be stored in a capped container to prevent degradation.
  
 
==Production==
 
==Production==
Line 24: Line 132:
  
 
Crude tetrachlorocupric acid can be made by mixing 2 moles of a strong acid, 1 mole of a copper salt, and 4 moles of a chloride source, preferably [[sodium chloride]] or [[potassium chloride]]. The [[spectator ions]] should not interfere. Do not use [[nitric acid]] for this, as it will create [[aqua regia]] and decompose. (Nitric acid itself works as a PCB etchant.)
 
Crude tetrachlorocupric acid can be made by mixing 2 moles of a strong acid, 1 mole of a copper salt, and 4 moles of a chloride source, preferably [[sodium chloride]] or [[potassium chloride]]. The [[spectator ions]] should not interfere. Do not use [[nitric acid]] for this, as it will create [[aqua regia]] and decompose. (Nitric acid itself works as a PCB etchant.)
 +
 +
==Projects==
 +
*PCB etching
 +
 +
==Handling==
 +
===Safety===
 +
Tetrachlorocupric acid is corrosive and poses some toxicity being a copper compound.
 +
 +
===Storage===
 +
In closed bottles.
 +
 +
===Disposal===
 +
Can be neutralize with any base.
 +
 +
==References==
 +
<references/>
 +
===Relevant Sciencemadness threads===
  
 
[[Category:Chemical compounds]]
 
[[Category:Chemical compounds]]
 
[[Category:Inorganic compounds]]
 
[[Category:Inorganic compounds]]
 
[[Category:Copper compounds]]
 
[[Category:Copper compounds]]
 +
[[Category:Coordination complexes]]
 +
[[Category:Copper complexes]]
 
[[Category:Acids]]
 
[[Category:Acids]]
 
[[Category:Oxidizing agents]]
 
[[Category:Oxidizing agents]]
 
[[Category:PCB etchants]]
 
[[Category:PCB etchants]]
 
[[Category:Easily prepared chemicals]]
 
[[Category:Easily prepared chemicals]]
 +
[[Category:Irritants]]
 +
[[Category:Materials stable only in solution]]

Latest revision as of 12:37, 25 June 2023

Stub.png This article is a stub. Please help Sciencemadness Wiki by expanding it, adding pictures, and improving existing text.
Tetrachlorocupric acid
Tetrachlorocupric acid with copper by Zts16.jpg
Tetrachlorocupric acid formed from copper metal, hydrochloric acid, and hydrogen peroxide as an intermediate in the synthesis of copper(II) chloride
Properties
H2CuCl4
Molar mass 207.37 g/mol
Appearance Green liquid (solution)
Melting point Decomposes
Boiling point Decomposes
Perfectly soluble, stable in acidic water
Solubility Insoluble in organic solvents, decomposes
Hazards
Safety data sheet None
Flash point Non-flammable
Related compounds
Related compounds
 Hydrochloric acid
Copper(II) chloride
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
Infobox references

Tetrachlorocupric acid is an acid formed from the tetrachlorocuprate ion. It is not stable as a solid, rather converting back to hydrochloric acid and copper(II) chloride. However, it is an extremely useful printed circuit board (PCB) etchant.

Properties

Chemical

When exposed to copper, the tetrachlorocuprate ion comproportionates with the copper metal to form the dichlorocuprate(I) ion:

CuCl42- + Cu → 2 CuCl2-

For simple etching, the presence of tetrachlorocuprate is enough to do the job. However, the acidity of tetrachlorocupric acid has the added bonus of allowing the solution to regenerate and be reused when exposed to air:

4 H+ + 8 Cl- + 4 CuCl2- + O2 → 4 CuCl42- + 2 H2O

This reaction can be accelerated by adding hydrogen peroxide.

Tetrachlorocuprates are able to dissolve many other metals, notably aluminum.

Physical

Tetrachlorocupric acid exists as a green solution due to the presence of tetrachlorocuprate ions. It is stable, but may emit some hydrogen chloride, so it should be stored in a capped container to prevent degradation.

Production

Pure tetrachlorocupric acid is not commerically available, but it can be made easily from hydrochloric acid and copper(II) chloride by mixing them together in a 2:1 molar ratio. It can also be made by dissolving copper(II) oxide, copper(II) carbonate, or copper(II) hydroxide in hydrochloric acid in a 4:1 molar ratio.

Crude tetrachlorocupric acid can be made by mixing 2 moles of a strong acid, 1 mole of a copper salt, and 4 moles of a chloride source, preferably sodium chloride or potassium chloride. The spectator ions should not interfere. Do not use nitric acid for this, as it will create aqua regia and decompose. (Nitric acid itself works as a PCB etchant.)

Projects

  • PCB etching

Handling

Safety

Tetrachlorocupric acid is corrosive and poses some toxicity being a copper compound.

Storage

In closed bottles.

Disposal

Can be neutralize with any base.

References

Relevant Sciencemadness threads

Retrieved from "https://www.sciencemadness.org/smwiki/index.php?title=Tetrachlorocupric_acid&oldid=15054"