Difference between revisions of "Chlorine"

From Sciencemadness Wiki
Jump to: navigation, search
(→‎Disposal)
 
(7 intermediate revisions by 2 users not shown)
Line 1: Line 1:
−
[[File:Chlorine_ampoule.jpg|thumb|320px|Chlorine gas in an ampoule.]]
+
{{Infobox element
−
'''Chlorine''' is the second-lightest [[halogen]], with the symbol '''Cl''' and atomic number 17. It has a sickly green colour and a distinctive smell, recognizable to many at low concentrations as 'the smell of pool centers' due to its compounds use as a water disinfecting agent.
+
<!-- top -->
 +
|image name=Chlorine_ampoule.jpg
 +
|image alt=
 +
|image size=300
 +
|image name comment=Chlorine gas in an ampoule.
 +
|image name 2=
 +
|image alt 2=
 +
|image size 2=
 +
|image name 2 comment=
 +
<!-- General properties -->
 +
|name=Chlorine
 +
|symbol=Cl
 +
|pronounce=
 +
|pronounce ref=
 +
|pronounce comment=
 +
|pronounce 2=
 +
|alt name=
 +
|alt names=
 +
|allotropes=
 +
|appearance= Greenish gas
 +
<!-- Periodic table -->
 +
|above=[[Fluorine|F]]
 +
|below=[[Bromine|Br]]
 +
|left=[[Sulfur]]
 +
|right=[[Argon]]
 +
|number=17
 +
|atomic mass=35.45
 +
|atomic mass 2=
 +
|atomic mass ref=
 +
|atomic mass comment=
 +
|series=Halogens
 +
|series ref=
 +
|series comment=
 +
|series color=
 +
|group= 17
 +
|group ref=
 +
|group comment=
 +
|period=17
 +
|period ref=
 +
|period comment=
 +
|block=p
 +
|block ref=
 +
|block comment=
 +
|electron configuration=[Ne] 3s<sup>2</sup> 3p<sup>5</sup>
 +
|electron configuration ref=
 +
|electron configuration comment=
 +
|electrons per shell=2, 8, 7
 +
|electrons per shell ref=
 +
|electrons per shell comment=
 +
<!-- Physical properties -->
 +
|physical properties comment=
 +
|color=Pale green
 +
|phase=Gas
 +
|phase ref=
 +
|phase comment=
 +
|melting point K=171.6
 +
|melting point C=−101.5
 +
|melting point F=−150.7
 +
|melting point ref=
 +
|melting point comment=
 +
|boiling point K=239.11
 +
|boiling point C=−34.04
 +
|boiling point F=​−29.27
 +
|boiling point ref=
 +
|boiling point comment=
 +
|sublimation point K=
 +
|sublimation point C=
 +
|sublimation point F=
 +
|sublimation point ref=
 +
|sublimation point comment=
 +
|density gplstp=3.2
 +
|density gplstp ref=
 +
|density gplstp comment=
 +
|density gpcm3nrt=
 +
|density gpcm3nrt ref=
 +
|density gpcm3nrt comment=
 +
|density gpcm3nrt 2=
 +
|density gpcm3nrt 2 ref=
 +
|density gpcm3nrt 2 comment=
 +
|density gpcm3nrt 3=
 +
|density gpcm3nrt 3 ref=
 +
|density gpcm3nrt 3 comment=
 +
|density gpcm3mp=
 +
|density gpcm3mp ref=
 +
|density gpcm3mp comment=
 +
|density gpcm3bp=1.5625
 +
|density gpcm3bp ref=
 +
|density gpcm3bp comment=
 +
|molar volume=
 +
|molar volume unit =
 +
|molar volume ref=
 +
|molar volume comment=
 +
|triple point K=
 +
|triple point kPa=
 +
|triple point ref=
 +
|triple point comment=
 +
|triple point K 2=
 +
|triple point kPa 2=
 +
|triple point 2 ref=
 +
|triple point 2 comment=
 +
|critical point K=416.9
 +
|critical point MPa=7.991
 +
|critical point ref=
 +
|critical point comment=
 +
|heat fusion=6.406
 +
|heat fusion ref=
 +
|heat fusion comment=
 +
|heat fusion 2=
 +
|heat fusion 2 ref=
 +
|heat fusion 2 comment=
 +
|heat vaporization=20.41
 +
|heat vaporization ref=
 +
|heat vaporization comment=
 +
|heat capacity=33.949
 +
|heat capacity ref=
 +
|heat capacity comment=
 +
|heat capacity 2=
 +
|heat capacity 2 ref=
 +
|heat capacity 2 comment=
 +
|vapor pressure 1=128
 +
|vapor pressure 10=139
 +
|vapor pressure 100=153
 +
|vapor pressure 1 k=170
 +
|vapor pressure 10 k=197
 +
|vapor pressure 100 k=239
 +
|vapor pressure ref=
 +
|vapor pressure comment=
 +
|vapor pressure 1 2=
 +
|vapor pressure 10 2=
 +
|vapor pressure 100 2=
 +
|vapor pressure 1 k 2=
 +
|vapor pressure 10 k 2=
 +
|vapor pressure 100 k 2=
 +
|vapor pressure 2 ref=
 +
|vapor pressure 2 comment=
 +
<!-- Atomic properties -->
 +
|atomic properties comment=
 +
|oxidation states='''7''', 6, '''5''', 4, 3, 2, '''1''', '''−1'''
 +
|oxidation states ref=
 +
|oxidation states comment=(a strongly acidic oxide)
 +
|electronegativity=3.16
 +
|electronegativity ref=
 +
|electronegativity comment=
 +
|ionization energy 1=1251.2
 +
|ionization energy 1 ref=
 +
|ionization energy 1 comment=
 +
|ionization energy 2=2298
 +
|ionization energy 2 ref=
 +
|ionization energy 2 comment=
 +
|ionization energy 3=3822
 +
|ionization energy 3 ref=
 +
|ionization energy 3 comment=
 +
|number of ionization energies=
 +
|ionization energy ref=
 +
|ionization energy comment=
 +
|atomic radius=
 +
|atomic radius ref=
 +
|atomic radius comment=
 +
|atomic radius calculated=
 +
|atomic radius calculated ref=
 +
|atomic radius calculated comment=
 +
|covalent radius=102±4
 +
|covalent radius ref=
 +
|covalent radius comment=
 +
|Van der Waals radius=175
 +
|Van der Waals radius ref=
 +
|Van der Waals radius comment=
 +
<!-- Miscellanea -->
 +
|crystal structure=
 +
|crystal structure prefix=
 +
|crystal structure ref=
 +
|crystal structure comment=Orthorhombic
 +
|crystal structure 2=
 +
|crystal structure 2 prefix=
 +
|crystal structure 2 ref=
 +
|crystal structure 2 comment=
 +
|speed of sound=
 +
|speed of sound ref=
 +
|speed of sound comment=
 +
|speed of sound rod at 20=
 +
|speed of sound rod at 20 ref=
 +
|speed of sound rod at 20 comment=
 +
|speed of sound rod at r.t.=
 +
|speed of sound rod at r.t. ref=
 +
|speed of sound rod at r.t. comment=
 +
|thermal expansion=
 +
|thermal expansion ref=
 +
|thermal expansion comment=
 +
|thermal expansion at 25=
 +
|thermal expansion at 25 ref=
 +
|thermal expansion at 25 comment=
 +
|thermal conductivity=8.9×10<sup>−3</sup>
 +
|thermal conductivity ref=
 +
|thermal conductivity comment=
 +
|thermal conductivity 2=
 +
|thermal conductivity 2 ref=
 +
|thermal conductivity 2 comment=
 +
|thermal diffusivity=
 +
|thermal diffusivity ref=
 +
|thermal diffusivity comment=
 +
|electrical resistivity=
 +
|electrical resistivity unit prefix=
 +
|electrical resistivity ref=
 +
|electrical resistivity comment=
 +
|electrical resistivity at 0=
 +
|electrical resistivity at 0 ref=
 +
|electrical resistivity at 0 comment=
 +
|electrical resistivity at 20=>10
 +
|electrical resistivity at 20 ref=
 +
|electrical resistivity at 20 comment=
 +
|band gap=
 +
|band gap ref=
 +
|band gap comment=
 +
|Curie point K=
 +
|Curie point ref=
 +
|Curie point comment=
 +
|magnetic ordering=Diamagnetic
 +
|magnetic ordering ref=
 +
|magnetic ordering comment=
 +
|tensile strength=
 +
|tensile strength ref=
 +
|tensile strength comment=
 +
|Young's modulus=
 +
|Young's modulus ref=
 +
|Young's modulus comment=
 +
|Shear modulus=
 +
|Shear modulus ref=
 +
|Shear modulus comment=
 +
|Bulk modulus=
 +
|Bulk modulus ref=
 +
|Bulk modulus comment=
 +
|Poisson ratio=
 +
|Poisson ratio ref=
 +
|Poisson ratio comment=
 +
|Mohs hardness=
 +
|Mohs hardness ref=
 +
|Mohs hardness comment=
 +
|Mohs hardness 2=
 +
|Mohs hardness 2 ref=
 +
|Mohs hardness 2 comment=
 +
|Vickers hardness=
 +
|Vickers hardness ref=
 +
|Vickers hardness comment=
 +
|Brinell hardness=
 +
|Brinell hardness ref=
 +
|Brinell hardness comment=
 +
|CAS number=7782-50-5
 +
|CAS number ref=
 +
|CAS number comment=
 +
<!-- History -->
 +
|naming=
 +
|predicted by=
 +
|prediction date ref=
 +
|prediction date=
 +
|discovered by=
 +
|discovery date ref=
 +
|discovery date=
 +
|first isolation by=
 +
|first isolation date ref=
 +
|first isolation date=
 +
|discovery and first isolation by=Carl Wilhelm Scheele (1774)
 +
|named by=
 +
|named date ref=
 +
|named date=
 +
|history comment label=
 +
|history comment=
 +
<!-- Isotopes -->
 +
|isotopes=
 +
|isotopes comment=
 +
|engvar=
 +
}}
 +
'''Chlorine''' is the second-lightest [[halogen]], with the symbol '''Cl''' and atomic number 17. It has a sickly green colur and a distinctive smell, recognizable to many at low concentrations as 'the smell of pool centers' due to its use as a water disinfecting agent.
  
 
==Properties==
 
==Properties==
 
===Chemical===
 
===Chemical===
−
Chlorine is a strong oxidizer with 7 valence [[electrons]]. Its unstable [[electron configuration]] results in high reactivity. Because of this, chlorine usually exists on earth in the form of a [[halide]] [[salt]], and free chlorine is rare. Like [[fluorine]], elemental chlorine forms a highly reactive [[diatomic molecule|diatomic gas]].<ref>"Handbook of Toxicology of Chemical Warfare Agents", Academic Press, 2009, p. 313.</ref> Chlorine, like other halogens, forms many [[oxoanion|oxoanions]], negatively charged ions containing oxygen. Most notably, these are [[hypochlorite]](ClO<sup>-</sup>), [[chlorite]](ClO<sub>2</sub><sup>-</sup>), [[chlorate]](ClO<sub>3</sub><sup>-</sup>), and [[perchlorate]](ClO<sub>4</sub><sup>-</sup>).
+
Chlorine is a strong oxidizer with 7 valence [[electron]]s. Its unstable [[electron configuration]] results in high reactivity. Because of this, chlorine usually exists on earth in the form of a [[halide]] [[salt]], and free chlorine is rare. Like [[fluorine]], elemental chlorine forms a highly reactive diatomic gas.<ref>"Handbook of Toxicology of Chemical Warfare Agents", Academic Press, 2009, p. 313.</ref> Chlorine, like other halogens, forms many [[oxoanion|oxoanions]], negatively charged ions containing oxygen. Most notably, these are [[hypochlorite]](ClO<sup>-</sup>), [[chlorite]](ClO<sub>2</sub><sup>-</sup>), [[chlorate]](ClO<sub>3</sub><sup>-</sup>), and [[perchlorate]](ClO<sub>4</sub><sup>-</sup>).
  
 
Unlike hydrochloric acid, elemental chlorine easily corrodes copper, especially in moist air.<ref>[https://books.google.ro/books?id=KXwgAZJBWb0C&pg=RA1-PT224&lpg=RA1-PT224&dq=chlorine+attacks+copper&source=bl&ots=RgG_xtytXk&sig=AlZHGGUonD_edLw6r6tj7vpXE84&hl=ro&sa=X&ei=_zGYVMDIAqahyAP3_YCoDQ&ved=0CCkQ6AEwAQ#v=onepage&q=chlorine%20attacks%20copper&f=false Handbook of Corrosion Data, by Bruce D. Craig, David S. Anderson, p. 271]</ref>
 
Unlike hydrochloric acid, elemental chlorine easily corrodes copper, especially in moist air.<ref>[https://books.google.ro/books?id=KXwgAZJBWb0C&pg=RA1-PT224&lpg=RA1-PT224&dq=chlorine+attacks+copper&source=bl&ots=RgG_xtytXk&sig=AlZHGGUonD_edLw6r6tj7vpXE84&hl=ro&sa=X&ei=_zGYVMDIAqahyAP3_YCoDQ&ved=0CCkQ6AEwAQ#v=onepage&q=chlorine%20attacks%20copper&f=false Handbook of Corrosion Data, by Bruce D. Craig, David S. Anderson, p. 271]</ref>
Line 20: Line 291:
  
 
[[Potassium permanganate]] will oxidize [[hydrochloric acid]] to chlorine gas, as will [[manganese dioxide]]. In both cases, [[manganese(II) chloride]] will be produced as well.
 
[[Potassium permanganate]] will oxidize [[hydrochloric acid]] to chlorine gas, as will [[manganese dioxide]]. In both cases, [[manganese(II) chloride]] will be produced as well.
 +
 +
: 2 KMnO<sub>4</sub> + 16 HCl → 2 KCl + 2 MnCl<sub>2</sub> + 5 Cl<sub>2</sub> + 8 H<sub>2</sub>O
  
 
A hypochlorite and hydrochloric acid will produce chlorine; either a solution of [[sodium hypochlorite]] or [[calcium hypochlorite]]. A violent reaction with a lot of foam may take place in the case of the latter, and starting small scale is a must to get a sense for the reaction before any large scale chlorine production is attempted.
 
A hypochlorite and hydrochloric acid will produce chlorine; either a solution of [[sodium hypochlorite]] or [[calcium hypochlorite]]. A violent reaction with a lot of foam may take place in the case of the latter, and starting small scale is a must to get a sense for the reaction before any large scale chlorine production is attempted.
 +
 +
: MOCl + HCl → MCl + Cl<sub>2</sub> + H<sub>2</sub>O
  
 
A popular way of making chlorine on Sciencemadness is using hydrochloric acid and [[trichloroisocyanuric acid]] (TCCA). TCCA can be found as slow release chlorine tablets for swimming pools. This reaction is favorable because it not too expensive, produces a large amount of chlorine over an extended period of time (while hypochlorites tend to violently produce all the chlorine right on mixing with the acid), leaves no awful byproducts (such as [[Manganese dioxide|MnO<sub>2</sub>]]) and the reaction speed at standard concentrations and temperatures is not too fast nor too slow for most applications.
 
A popular way of making chlorine on Sciencemadness is using hydrochloric acid and [[trichloroisocyanuric acid]] (TCCA). TCCA can be found as slow release chlorine tablets for swimming pools. This reaction is favorable because it not too expensive, produces a large amount of chlorine over an extended period of time (while hypochlorites tend to violently produce all the chlorine right on mixing with the acid), leaves no awful byproducts (such as [[Manganese dioxide|MnO<sub>2</sub>]]) and the reaction speed at standard concentrations and temperatures is not too fast nor too slow for most applications.
Line 27: Line 302:
 
==Projects/Experiments==
 
==Projects/Experiments==
 
Chlorine can be used to produce anhydrous metal chlorides, such as [[Aluminium chloride|aluminum(III) chloride]], [[iron(II) chloride|iron(II)]] or [[iron(III) chloride]], and many others, which cannot be made in solution, due to formation of hydrates which are irreversible, and decompose to the metal oxide and HCl gas upon heating.
 
Chlorine can be used to produce anhydrous metal chlorides, such as [[Aluminium chloride|aluminum(III) chloride]], [[iron(II) chloride|iron(II)]] or [[iron(III) chloride]], and many others, which cannot be made in solution, due to formation of hydrates which are irreversible, and decompose to the metal oxide and HCl gas upon heating.
−
:2 Al + 3 Cl<sub>2 </sub> → 2 AlCl<sub>3</sub>
+
 
−
:2 Fe + 3 Cl<sub>2 </sub> → 2 FeCl<sub>3</sub>
+
: 2 Al + 3 Cl<sub>2</sub> → 2 AlCl<sub>3</sub>
 +
: 2 Fe + 3 Cl<sub>2</sub> → 2 FeCl<sub>3</sub>
  
 
Other projects:
 
Other projects:
 
*Make hypochlorites
 
*Make hypochlorites
−
*Make [[sulfur dichloride]]
+
*Make [[sulfur dichloride]] and [[disulfur dichloride]]
−
*Make [[disulfur dichloride]]
+
 
*Make interhalogen compounds
 
*Make interhalogen compounds
 
*Alkane halogenation
 
*Alkane halogenation
 +
*Element collecting
  
 
==Handling==
 
==Handling==
 
===Safety===
 
===Safety===
−
Elemental chlorine is extremely toxic and corrosive to many common metals. Because it is heavier than air, it tends to accumulate at the bottom of poorly ventilated spaces. Chlorine gas is a strong oxidizer, which may react with flammable materials. It is notorious for reacting with iron at high temperatures, in a strong exothermic reaction, known as chlorine-iron fire.
+
Elemental chlorine is extremely toxic and corrosive to mot materials, be it organic or inorganic. Because it is heavier than air, it tends to accumulate at the bottom of poorly ventilated spaces. It is highly irritant to eyes, mucous membrane, throat and lungs, even short term exposure may cause injury.
 +
 
 +
Chlorine gas is a strong oxidizer, which may react with flammable materials. It is notorious for reacting with iron at high temperatures, in a strong exothermic reaction, known as chlorine-iron fire.
  
 
===Storage===
 
===Storage===
Line 49: Line 327:
  
 
===Disposal===
 
===Disposal===
−
As it is toxic and has an irritating smell, it is recommended to neutralize chlorine before disposing of it. In gaseous form, elemental chlorine can be neutralized with ammonia, reaction that produces nitrogen gas and [[ammonium chloride]].
+
As it is toxic and has an irritating smell, it is recommended to neutralize chlorine before disposing of it. In gaseous form, elemental chlorine can be neutralized with ammonia at low concentrations, reaction that produces nitrogen gas and [[ammonium chloride]], though chloramines may also be produced as side products. This should not be used at high concentrations of chlorine in air, where chloramines may be produced in higher amount.
  
−
Aqueous chlorine however, should never be neutralized with ammonia, as it will generate toxic chloramines. Acids should also be avoided. Hydrogen peroxide will neutralize bleach and release oxygen. Ascorbic acid and its salts are also good at neutralizing chlorine. Other good neutralizing agents are certain sulfur compounds, such as bisulfites, metabisulfites, thiosulfites.
+
Aqueous chlorine however, should never be neutralized with ammonia, as it will generate toxic chloramines. Acids should also be avoided. Hydrogen peroxide will neutralize bleach and release oxygen. Ascorbic acid and its salts are also good at neutralizing chlorine. Other good neutralizing agents are certain sulfur compounds, such as sulfites, bisulfites, metabisulfites, thiosulfites.
 +
 
 +
==Gallery==
 +
<gallery widths="200" position="center" columns="4" orientation="none">
 +
Liquid_chlorine.jpg|A sample of liquid chlorine
 +
</gallery>
  
 
==References==
 
==References==
 
<references />
 
<references />
 
===Relevant Sciencemadness threads===
 
===Relevant Sciencemadness threads===
 +
*[http://www.sciencemadness.org/talk/viewthread.php?tid=9713 Chlorine - Illustrated Practical Guide]
 +
*[http://www.sciencemadness.org/talk/viewthread.php?tid=11259 Best overall chlorine generator?]
 +
*[http://www.sciencemadness.org/talk/viewthread.php?tid=22473 Making Chlorine]
 +
*[http://www.sciencemadness.org/talk/viewthread.php?tid=730 Preparation of Chlorine]
 +
*[http://www.sciencemadness.org/talk/viewthread.php?tid=17336 Small scale chlorine generation.]
 +
*[http://www.sciencemadness.org/talk/viewthread.php?tid=66003 Passing chlorine gas]
 +
*[http://www.sciencemadness.org/talk/viewthread.php?tid=24318 Found an easy way to make chlorine gas from muriatic acid and bleach]
 +
*[http://www.sciencemadness.org/talk/viewthread.php?tid=61768 Ways to get pure chlorine gas in a container/separate from the generator]
 +
*[http://www.sciencemadness.org/talk/viewthread.php?tid=66219 What to do with chlorine gas ?]
 +
*[http://www.sciencemadness.org/talk/viewthread.php?tid=29102 Storing Chlorine as a liquid?]
 
*[http://www.sciencemadness.org/talk/viewthread.php?tid=36860 Chlorine gas neutralization]
 
*[http://www.sciencemadness.org/talk/viewthread.php?tid=36860 Chlorine gas neutralization]
 +
 
[[Category:Elements]]
 
[[Category:Elements]]
−
[[Category:Halogens]]
 
−
[[Category:Oxidizing agents]]
 
 
[[Category:Diatomic elements]]
 
[[Category:Diatomic elements]]
−
[[Category:Gases]]
 
 
[[Category:Nonmetals]]
 
[[Category:Nonmetals]]
 +
[[Category:Halogens]]
 
[[Category:P-block]]
 
[[Category:P-block]]
 +
[[Category:Oxidizing agents]]
 
[[Category:Chlorinating agents]]
 
[[Category:Chlorinating agents]]
 
[[Category:Choking agents]]
 
[[Category:Choking agents]]
 +
[[Category:Gases]]

Latest revision as of 17:48, 8 November 2023

Chlorine,  17Cl
Chlorine ampoule.jpg
Chlorine gas in an ampoule.
General properties
Name, symbol Chlorine, Cl
Appearance Greenish gas
Chlorine in the periodic table
F
↑
Cl
↓
Br
Sulfur ← Chlorine → Argon
Atomic number 17
Standard atomic weight (Ar) 35.45
Group, block , p-block
Period period 17
Electron configuration [Ne] 3s2 3p5
per shell
 2, 8, 7
Physical properties
Pale green
Phase Gas
Melting point 171.6 K ​(−101.5 °C, ​−150.7 °F)
Boiling point 239.11 K ​(−34.04 °C, ​​−29.27 °F)
Density at  (0 °C and 101.325 kPa) 3.2 g/L
when liquid, at  1.5625 g/cm3
Critical point 416.9 K, 7.991 MPa
Heat of fusion 6.406 kJ/mol
Heat of 20.41 kJ/mol
Molar heat capacity 33.949 J/(mol·K)
 pressure
Atomic properties
Oxidation states 7, 6, 5, 4, 3, 2, 1, −1 ​(a strongly acidic oxide)
Electronegativity Pauling scale: 3.16
energies 1st: 1251.2 kJ/mol
2nd: 2298 kJ/mol
3rd: 3822 kJ/mol
Covalent radius 102±4 pm
Van der Waals radius 175 pm
Miscellanea
Crystal structure ​Orthorhombic
Thermal conductivity 8.9×10−3 W/(m·K)
Electrical resistivity >10 Ω·m (at 20 °C)
Magnetic ordering Diamagnetic
CAS Registry Number 7782-50-5
Discovery and first isolation Carl Wilhelm Scheele (1774)
· references

Chlorine is the second-lightest halogen, with the symbol Cl and atomic number 17. It has a sickly green colur and a distinctive smell, recognizable to many at low concentrations as 'the smell of pool centers' due to its use as a water disinfecting agent.

Properties

Chemical

Chlorine is a strong oxidizer with 7 valence electrons. Its unstable electron configuration results in high reactivity. Because of this, chlorine usually exists on earth in the form of a halide salt, and free chlorine is rare. Like fluorine, elemental chlorine forms a highly reactive diatomic gas.[1] Chlorine, like other halogens, forms many oxoanions, negatively charged ions containing oxygen. Most notably, these are hypochlorite(ClO-), chlorite(ClO2-), chlorate(ClO3-), and perchlorate(ClO4-).

Unlike hydrochloric acid, elemental chlorine easily corrodes copper, especially in moist air.[2]

Physical

Chlorine is a yellow-greenish gas, with a powerful odor similar to that of boiling hypochlorite solutions. It is heavier than air, and slightly soluble in water, 3.26 g/L.

Availability

While liquid (as in liquefied, and not aqueous solution) chlorine is sold by gas companies, it is hard to get hold of as it's very toxic and corrosive.

Chlorine is better produced from OTC products.

Production

There are many methods to generating chlorine gas, due to it being such a commonly used ion.

Potassium permanganate will oxidize hydrochloric acid to chlorine gas, as will manganese dioxide. In both cases, manganese(II) chloride will be produced as well.

2 KMnO4 + 16 HCl → 2 KCl + 2 MnCl2 + 5 Cl2 + 8 H2O

A hypochlorite and hydrochloric acid will produce chlorine; either a solution of sodium hypochlorite or calcium hypochlorite. A violent reaction with a lot of foam may take place in the case of the latter, and starting small scale is a must to get a sense for the reaction before any large scale chlorine production is attempted.

MOCl + HCl → MCl + Cl2 + H2O

A popular way of making chlorine on Sciencemadness is using hydrochloric acid and trichloroisocyanuric acid (TCCA). TCCA can be found as slow release chlorine tablets for swimming pools. This reaction is favorable because it not too expensive, produces a large amount of chlorine over an extended period of time (while hypochlorites tend to violently produce all the chlorine right on mixing with the acid), leaves no awful byproducts (such as MnO2) and the reaction speed at standard concentrations and temperatures is not too fast nor too slow for most applications.

Projects/Experiments

Chlorine can be used to produce anhydrous metal chlorides, such as aluminum(III) chloride, iron(II) or iron(III) chloride, and many others, which cannot be made in solution, due to formation of hydrates which are irreversible, and decompose to the metal oxide and HCl gas upon heating.

2 Al + 3 Cl2 → 2 AlCl3
2 Fe + 3 Cl2 → 2 FeCl3

Other projects:

Handling

Safety

Elemental chlorine is extremely toxic and corrosive to mot materials, be it organic or inorganic. Because it is heavier than air, it tends to accumulate at the bottom of poorly ventilated spaces. It is highly irritant to eyes, mucous membrane, throat and lungs, even short term exposure may cause injury.

Chlorine gas is a strong oxidizer, which may react with flammable materials. It is notorious for reacting with iron at high temperatures, in a strong exothermic reaction, known as chlorine-iron fire.

Storage

Liquefied chlorine must be stored in cold places, away from any source of heat. Chlorine can be liquefied at room temperature, at a pressure of 7.4 bar.

Chlorine releasing chemicals, such as bleach and TCCA should be stored in closed bottles, usually covered with a bag or in a box, that must be opened form time to time to release the pressure.

The storage area for both chemicals should not contain any metal parts susceptible to chlorine attack.

Disposal

As it is toxic and has an irritating smell, it is recommended to neutralize chlorine before disposing of it. In gaseous form, elemental chlorine can be neutralized with ammonia at low concentrations, reaction that produces nitrogen gas and ammonium chloride, though chloramines may also be produced as side products. This should not be used at high concentrations of chlorine in air, where chloramines may be produced in higher amount.

Aqueous chlorine however, should never be neutralized with ammonia, as it will generate toxic chloramines. Acids should also be avoided. Hydrogen peroxide will neutralize bleach and release oxygen. Ascorbic acid and its salts are also good at neutralizing chlorine. Other good neutralizing agents are certain sulfur compounds, such as sulfites, bisulfites, metabisulfites, thiosulfites.

Gallery

  • A sample of liquid chlorine

References

  1. ↑ "Handbook of Toxicology of Chemical Warfare Agents", Academic Press, 2009, p. 313.
  2. ↑ Handbook of Corrosion Data, by Bruce D. Craig, David S. Anderson, p. 271

Relevant Sciencemadness threads

Retrieved from "https://www.sciencemadness.org/smwiki/index.php?title=Chlorine&oldid=15373"