Interhalogen compounds preparation and properties, Group 17 P Block Elements

Interhalogen compounds preparation and properties, Group 17 P Block Elements

Interhalogen Compounds :

→ Halogene have tendency to react with the other members of group 17. This tendency is due to the difference in their electonegativities. These halogens combine with each other and form binary covalent compounds.

Interhalogen compounds preparation and properties, Group 17 P Block Elements

→ These compounds are known & interhalogen compounds. These interhalogen compounds are of AB, type where A is always bigger atom with low electronegativity while Bis smaller atom with high electronegativity. Here may be 1, 3, 5 and 7.

Interhalogen compounds are of four type:

  • AB type – CIF, BrF, BrCl, ICl, IBr
  • AB type – CIF3 BrF3, ICI3
  • AB type – BrF5, IF5
  • AB type – IF7

The name of these interhalogen compounds is written as:

  • The halogen with positive oxidation state is named as such with oxidation number in roman numeral in parenthe
  • The halogen with negative oxidation state is named as halide.

Interhalogen compounds preparation and properties, Group 17 P Block Elements

For example:

  • B-C-Bromine (I) chloride
  • ICI3 – lodine trichloride or iodine (III) chloride
  • IF7 – Iodine heptachloride or iodine (VII) chloride
  • ICI5 – Iodine penta chloride or iodine (V) chloride

Preparation :

→ Except IF7 generally all the interhalogen compounds can be prepared by direct combination of hakene under specific conditions. Some preparations are as follows:

Interhalogen compounds preparation and properties, Group 17 P Block Elements 1
Interhalogen compounds preparation and properties, Group 17 P Block Elements 2

Higher interhalogen can also be prepared by reacting lower interhalogen with ha1oens.

Interhalogen compounds preparation and properties, Group 17 P Block Elements 3

Structure of interhalogen compounds

→ AB Type: In this type of interhalogen compounds the bigger halogen atom is sp3 hybridised. It has tetrahedral geometrical linear abape. In tetrahedral geometry three hybrid orbitals contain one lone pair of electron each while the fourth sp3 hybridised orbital overlap with porbital of another halogen. Thus, the shape becomes linear :

Interhalogen compounds preparation and properties, Group 17 P Block Elements 4

→ AB3 Type : In this type of interhalogen compounds the bigger halogen atom is sp3 d hybridised. It has triangular bipyramidal geometry and bent T shape. In sp3 d orbitale two hybrid orbitals have lone pair of electron while other three hybrid orbitals overlap with porbital of halogen atom.

Interhalogen compounds preparation and properties, Group 17 P Block Elements 5

→ AB5 Type : In this type of interhalogen compounds the bigger halogen atom is sp3 d2 hybridised. It has octahedral geometry and square pyramidal shape. In sp3d2 hybridised orbitals one has lone pair of electron while other five hybrid orbitals overlap with porbital of halogen atom.

Interhalogen compounds preparation and properties, Group 17 P Block Elements 6

→ AB7 Type : In this type of interhalogen compounde the bigger halogen atom is sp3d3 hybridised. It has pentagonal hipyramidal shape.

Interhalogen compounds preparation and properties, Group 17 P Block Elements 7

Properties of interhalogen compounds

→ Some important properties of interhalogen compounds are as follows:

  • Interhalogen compounds are calent compounds
  • Due to abschce of unpaired electrons they are diamagnetle in nature.
  • They are very good oxidising agents.

Interhalogen compounds like ClF, BrF, ClF3 IF7 are gases while BrF3, BrF5, IF5 are liquid and ICl, IBr, IF3, ICI3, are solids in nature.

Interhalogen compounds preparation and properties, Group 17 P Block Elements

→ Some interhalogen compounds of fluorine are colourless while others are generally coloured. The colour become deeper with increase in molecular weight of compound.

→ The thermal stability of interhalogen compounds of the type AB increases with increase in electronegativity difference between A and B Higher the polarity of bond higher will be thermal stability.

IF > BrF > CIF >ICI > IBe > BrCl (Thermal stability)

→ Interhalogen compounds are more reactive than the constituent halogene because 4-B bond is relatively weaker than AABB bond due to difference in electronegativities. The order of reactivity of some interbelogen compounds are as follows: CIF3 > BrF5 > IF7 > BrF5 > IF5 > BeF (Reactivity order)

Interhalogen compounds preparation and properties, Group 17 P Block Elements

→ Interhalogen compounds are generally ionised in liquid state or in solution. For example,

Interhalogen compounds preparation and properties, Group 17 P Block Elements 8

→ Hydrolysis of interhalogen compounds give halogen acid and oxyhalogen acid. The oxyhalogen acid is of bigger halogen atom.

Interhalogen compounds preparation and properties, Group 17 P Block Elements 9

→ Interhalogens react with alkali metal halides forming polyhalides.

  • ICl + KBr → K+ [IBrCl]
  • ICl + KCl → K+ [ICl2]
  • ICI3 + KCl → K+ [ICl4]
  • IF5 + CsF → Cs+[IF6]
  • BrCl + CsI → Cs+ [IBrCl]
  • IBr + NaBr → Na+[IBr2]

→ Interhalogen compounds react with metallic and non metallic oxides as follows:

  • 3SiO2 + 4BrF3 → 3SiF4 + 2Br2 + 3O2
  • 2WO3 + 4BrF3 → 2WF6 + 2Br2 + 3O2

→ Interhalogen compounds of fluorine behave as good fluorinating agents.

  • 3UO2 + 4BrF3 → 3UF4 + 2Br2 + 3O2
  • UF4 + ClF3 → UF6 + ClF

→ Important characteristics of interhalogen compounds are summarised in Table 7.14

Important Characteristics of iriterhalogen compounds

Interhalogen compounds preparation and properties, Group 17 P Block Elements 10

Use of Interhalogen compounds

→ Interhalogen compounds can be used.

  • As non-aqueous solvents.
  • As a good fluorinating agents. For example, BrF3 and ClF3 are used to produce UF6.

U(g) + 3ClF3 → 3ClF + UF6

  • Chlorofluorocarbons, known as Preons, are used as refrigerants.

Interhalogen compounds preparation and properties, Group 17 P Block Elements

Example:

  • Freon – 11 is CCl3
  • Freon – 12 is CCl2F2
  • Freon – 13 is CClF3

Chemistry Notes

Oxoacids of halogens preparation and properties, Group 17 P Block Elements

Oxoacids of halogens preparation and properties, Group 17 P Block Elements

Oxo Acids of Halogens :

→ Halogens have high electronegativity so they have tendency to form oxo acids. But among all halogens fluorine have highest electronegativity and small size so it form only one oxo acid.

→ It is hypofluorous acid (HOF or HFO), Chlorine, Bromine and lodine form four types of Oxy acids, they are HXO, HXO2, HXO3 and HXO4. Among all these oxo acids few are quite unstable. They exist only in their alt solutions. The important oxoacids are given in table 7.20.

Oxoacids of halogens preparation and properties, Group 17 P Block Elements

Table 7.20 Some oxo acids of Halogens

Name Fluorine Chlorine Bromine Iodine
Halic (I) acid OR Hypohalous acid HOF (Hypo fluoro us acid) HOCl Hypochloro us acid HOBr Hypobromo us acid HOI Hypoiodous acid
Halic (III) acid OR Halous acid HOClO or HClO2 Chlorous acid
Halic (V) acid OR Halic acid HOClO2 or HClO3 Chloric acid HOBrO2 or HBrO3 Bromic acid HOIO2 or HIO3 Iodic acid
Halic (VII) acid OR Perhalic acid HOClO3 or HClO4 Perchloric acid HOBrOg or HBrO4 Perbromic acid HOIO3 or HIO4 Periodic acid

Structure of oxo acids of Chlorine

Oxoacids of halogens preparation and properties, Group 17 P Block Elements 1

Oxoacids of halogens preparation and properties, Group 17 P Block Elements 2

Acidic strength of oxoacids of halogens

→ Acidie strength of hypohalous acids: The acidic strength of hypohalous acids decreases with increase in atomic number because electronegativity decreased

HClO > HBrO > HIO (Acidic strength)

Oxoacids of halogens preparation and properties, Group 17 P Block Elements

→ Higher the electronegativity higher will be the tendency to attract electons hences the tendency to release H ion from O – H bond incore and acidity incrase.

→ Acidic strength of perhalic acid : The acidic strength of perhalic acid decreases as electronegativity decre

HClO4 > HBrD4 > HIO4 (Acidic strength)

Because as electronegativity decreases the tendency to withdraw electron form O – H XO3 group decreases hence acidie strength decreases.

→ Acidie strength of oxo Acids. The acidic strength of oxoacids of the same halogen increases with increase in oxidation number.

Oxoacids of halogens preparation and properties, Group 17 P Block Elements 3

→ The above order of acidie strength can be explained on the basic principle of Bronsted-lowry concept. This concept states that a strong acid will have a weak conjugate base while a weak acid will have a strong eonjugate bare The four conjugate base of oxo acids are

ClO, ClO2 ClO3, ClO4. The stability of these conjugate bases are as follows:
OCl < ClO2 < ClO3 < ClO4 (Stability)

Oxoacids of halogens preparation and properties, Group 17 P Block Elements

→ The stability of above given conjugate base anions depend upon the delocalisation of charge between oxygen atoms. Larger the dekealisation of charge higher the stability of conjugate base anion, lesser will be tendency to attract proton.

→ Hence, the conjugate base will behave as weaker base. But according to Bronsted-Lowery concept stronger the conjucate base weaker will be acid and vice versa. Now the charge delocalisation between oxygen atoms can be shown in fig. 7.42 by the dotted lines.

Oxoacids of halogens preparation and properties, Group 17 P Block Elements 4

→ The charge delocalisation or stabilisation is minimum in ClO and maximum in ClO4. Hence, order of charge stabilisation is as follow:

ClO < ClO2 < ClO3 < ClO4 (Charge stabilisation)

Oxoacids of halogens preparation and properties, Group 17 P Block Elements

→ From above discussion, we can conclude that ClO har minimum stability therefore it will have maximum tendency to attract the H+ ion i.c.. ClO is strongest Bronsted base so HClO is weakest acid. On the other hand ClO4 is weakest Brunsted base 0 HClO4 is the strongest acid.

HClO < CHClO2 <HClO3 < HClO4 (Acidic strength)

Oxidising power of oxoacids

→ Oxidising power of hypohalous acid: As the size of halogen increases the thermal stability of O – X bond increases but oxidising power of hypohalous acid or hypohalite ion decreases. The order of oxidising power is as follows:

OCl ≈ OBr > OI (Oxidising power)

→ The above order of oxidising power is supported by their electrode potentials.

Oxoacids of halogens preparation and properties, Group 17 P Block Elements 5

→ Oxidising power of perhalic acid. The ion of perhalie acid is perhalates. Perhalates are very strong oxidising agent. Their oxidising power is as follows:

BrO4 > IO4 > ClO4 (Oxidising power)

→ The above order is on the basis of values of electrode potentials which are as follows:

Oxoacids of halogens preparation and properties, Group 17 P Block Elements 6

→ BrO4 is the strongest oxidising agent but it is weaker than F2

BrO3 + F2 + 2OH – BrO4 + 2F + H2O

Oxoacids of halogens preparation and properties, Group 17 P Block Elements

→ Oxidising power of halous acids: As the stability of relative anions of acid increases the oxidising power decreases. Thus,

HClO4 < HClO3 < HClO2 HClO (Oxidising power)

Chemistry Notes

Hydrogen chloride preparation and properties, Group 17 P Block Elements

Hydrogen chloride preparation and properties, Group 17 P Block Elements

Hydrogen Chloride (HCl) :

→ Hydrogen chloride is a major industrial chemical. It is widely used as laboratory regent. First time in 1648 Glauber prepared it by heating the common salt (NaCl) with concentrated sulphuric acid (H2SO4).

Hydrogen chloride preparation and properties, Group 17 P Block Elements

→ In 1810, Davy proved that it is a compound of hydrogen and chlorine. When hydrogen combines with chlorine then a covalent compound HCl is formed. In anhydrous state it is not acidic in nature but in aqueous state it release H+ lona thus, it is also called hydrogen acids or hydra acid. Priestely called it ‘marine acid’ and Lavoisier called it ‘Quriotic acid’.

Preparation :

It can be prepared by the following methods:

→ Laboratory Method : In laboratory, it can be prepared by heating sodium chloride (rock salt) with concentrated sulphuric acid.

Hydrogen chloride preparation and properties, Group 17 P Block Elements 1

It can be dried by passing it through concentrated sulphuric acid

→ Above process can also be used for commercial preparation Commercially it can be manufactured by heating NaCl and conc. H2SO4 in Muffle furnace.

Hydrogen chloride preparation and properties, Group 17 P Block Elements

→ By ammonium chloride : When ammonium chloride is heated with consulphuric acid then HCl is formed

2NH4 + Cl + H2SO4 → (NH4)2 SO4 + 2HCl

→ Industrial preparation in large scale HCI can be prepared as a byproduct from the heavy organic industry. It can be prepared during the conversion of 1.2.dichloroethane into vinyl chloride

Hydrogen chloride preparation and properties, Group 17 P Block Elements 2

Physical properties of Hydrogen chloride

Some important physical properties of hydrogen chloride are as follows:

  • It is colourlons, pungent Amelling gas
  • It can easily be liquified into colorless liguid
  • It is highly soluble in water and its aqueous solution is known as hydrochloric acid
  • It fumes in moist air.
  • Its boiling point is 189K
  • It freezes into white crystalline solid. Its freezing points in 169 K
  • It is heavier than air. Itu vapour density is 18.25.

Chemical properties of Hydrogen chloride

→ Action on Htmus : Dry HCL cannot chnage the colour of litmus but its aqueous solution can tum blue litmus red which indicates that it is acidic in nature.

→ Acidic behaviour. In aqueous solution it ionises and produce hydronium ion (H3O+) and chloride ion (Cl)
HCl(g) + H2O(l) → H3O+(aq) + Cl(aq), Ka = 107

Hydrogen chloride preparation and properties, Group 17 P Block Elements

→ Its dissociation constant (Ka) is very high which indicates that it is a very strong acid in water. Some acidic properties of hydrochloric acid are as follows:

→ Reaction with metals: It reacts with active metals like sodium, potassium, magnesium, iron zinc etc. and liberate hydrogen gas :

Hydrogen chloride preparation and properties, Group 17 P Block Elements 3

→ Reaction with ammonia: It reacts with ammonia and give white fumes of NH4Cl.

Hydrogen chloride preparation and properties, Group 17 P Block Elements 4

→ Reaction with bases : It reacts with bases like hydroxides, carbonates, bicarbonate of metals to form chlorides

Hydrogen chloride preparation and properties, Group 17 P Block Elements 5

→ Reaction with salts : HCl can decomposes the salts like Na2S, NaNO2, Ca3P2, Na2SO3 etc.

Hydrogen chloride preparation and properties, Group 17 P Block Elements 6

→ Precipitation Reactions : HCl can form the precipitate of chlorides when it reacts with salts of Ag. Pb and Hg.

Hydrogen chloride preparation and properties, Group 17 P Block Elements 7

→ Reaction with fluorine : Fluorine can displace chlorines from HCl

2HCl + F2 → 2HF + Cl2

Hydrogen chloride preparation and properties, Group 17 P Block Elements

→ Oxidation : HCl can be oxidised by atmospherie oxygen in the presence of Cu2Cl2 catalyst at 723K temperature to produce chlorine PR This reaction is used in Deacon’s process.

Hydrogen chloride preparation and properties, Group 17 P Block Elements 8

→ As a reducing agent : It behaves as a reducing agent because it can be oxidised into chlorine by strong oxiding agents such as K2Cr2O7, KMnO4, MnO2 etc.

Hydrogen chloride preparation and properties, Group 17 P Block Elements 9

→ Formation of Aqua regia: A mixture of three parts of concentrated hydrochloric acid and one part of concentrated nitric acid is known as aqua regia. In aqua regia HCl acts as reducing Agent while HNO acts us oxidising agent. Aqua regin is used to dissolve noble metals Nike Au, Ptete.

Hydrogen chloride preparation and properties, Group 17 P Block Elements 10

Uses of Hydrogen chloride

  • In manufacturing of dyestuffs and in sugar industry.
  • In preparation of chlorine, ammonium chloride, metal chlorides etc.
  • In preparation of aqua regia.
  • In medicine and used as laboratory reagent.
  • For extracting glue from animal tissues and bones.
  • In pickling or cleaning metallic surfaces ie surface of oxide layer over metal before subjecting it for tin plating, galvanising and electroplating.

Chemistry Notes

Chlorine preparation and properties, Group 17 P Block Elements

Chlorine preparation and properties, Group 17 P Block Elements

Chlorine :

→ The first isolated halogen, was discovered by Scheele in 1774. He discovered it by the action of HCl on MnO2. In 1810. Davy described its elementary nature and he suggested the name chlorine on behalf of its colour.

→ Chlorine is a Greek word taken from chlorous meaning yellowish green. In 1785, Berthollet put its technical use. Chlorine is widely distributed in the form of chlorides of different metals in nature. One of the common example of it is common salt (NaCl).

Chlorine preparation and properties, Group 17 P Block Elements

Occurrence :

Chlorine is highly reactive no it does not occur in native state. About 0.19% part of lithosphere is constituted by it. In nature it occurs mainly in the form of chlorides of sodium and other alkali as well as alkaline earth metals. The most abundant compound of chlorine is common salt (NaCl). NaCl is found in saline Inkes, brines, oceans etc. Other minerals of chlorine Are Carnallite (KCl. MgCl2 . 6H2O), Sylvine (KCl) etc.

Preparation :

Some important method of preparations of chlorine are as follows:

→ By manganese dioxide: When manganese dioxide is heated with concentrated hydrochloric acid then chlorine is prepared.

MnO2 + 4HCl → MnCl2 + Cl2 + 2H2O

→ If manganese dioxide is heated with common salt and concentrated H2 SO4 then chlorine is prepared.

4NaCl + MnO2 + 4H2SO4 → MnCl2 + 4NaHSO4 + 2H2O + Cl2

Chlorine preparation and properties, Group 17 P Block Elements

→ By potassium permanganate : When potassium permanascanate is beated with hydrochloric acid (HCl) chlorine gas is formed.

Chlorine preparation and properties, Group 17 P Block Elements 1

→ By Potassium dichromate : When potassium dichromate to beated with hydrochloric acid then chlorine gas is formed.

K2Cr2O7 + 14HCl 2KCl + 2CrCl3+ 3Cl2 + 7H2O

By lead oxides. When lead oxide reacts with hydrochloric acid then chlorine gas is formed.

Chlorine preparation and properties, Group 17 P Block Elements 2

→ By Bleaching Powder By the action of HCl on bleaching powder chlorine is formed:

Chlorine preparation and properties, Group 17 P Block Elements 3

Commercial manufacturing of chlorine i Commercially chlorine gas can be manufactured by the following process:

→ Deacon’s process: In this procesa hydrochloric acid is oxidised by atmospheric air in the presence of Cuci, catalyst at 723 K temperature.

Chlorine preparation and properties, Group 17 P Block Elements 4

→ The above method is now modified by using improved catalvat Cuci with didymium oxide as promoter; didymium is old name whose meaning is in’ bere two lanthanoidsie.praseodymium and neodymium is used simultaneously.

→ Electrolytic process: By the electrolysis of brine soulution (sodium chloride solution) chlorine is obtained as by product at anode.

Chlorine preparation and properties, Group 17 P Block Elements 5

It can also be obtained as a by product during the manufacturing of sodium by electrolysis of fused NaClin Down’s Process

Physical Properties of Chlorine

  • It has pungent and suffocating odour
  • It is a greenish yellow gas.
  • It is about 2.5 time heavier than air.
  • It can easily be liquified into greenish yellow liquid. Its boiling point is 239 K.
  • It is soluble in water, It forms chlorine water which is a strong excidising agent.
  • It is poisonous in nature. If it is inhaled in small quantity then it causes headache. If it is inhaled in large quantity then it may prove to be deadly
  • Its meling point is 171K.

Chemical properties of Chlorine

Its important chemical properties are as follows:

→ Action on litmus. There is no effect of dry chkirine on litmus paper but moist chlorine may turn blue litmus red which is due to the presence of HCl and HClO in it.

Chlorine preparation and properties, Group 17 P Block Elements 6

→ Affinity for hydrogen : It does not combine with hydrogen in dark but in presence of sunlight it combines with hydrogen explosively.

Chlorine preparation and properties, Group 17 P Block Elements 7

→ Reaction with water: Since it has great affinity for bydrogen hence it decomposes water in presence of sunlight to produce HCl.

Chlorine preparation and properties, Group 17 P Block Elements 8

→ Reaction with ammonia : It reacts with ammonia in two ways

When ammonia is taken in exces, then nitrogen is formed

Chlorine preparation and properties, Group 17 P Block Elements 9

When chlorine is taken in excess, then nitrogen trichloride is formed.

Chlorine preparation and properties, Group 17 P Block Elements 10

Reaction with Metals :

→ With very active metals like sodium, chlorine etc. it burn in the atmosphere of chlorine to form their chlorides.

  • 2Na + Cl2 → 2NaCl
  • Ca + Cl2 → CaCl2

Chlorine preparation and properties, Group 17 P Block Elements

→ With less active metals like iron, aluminium, zinc, copper etc it reacts only on heating

Chlorine preparation and properties, Group 17 P Block Elements 11

Reaction with Alkalies Chlorine reacts with alkalies in different ways.

→ With cold and dilute With Cold and dilute alkalier. chlorine reacts to form chlorides and hypochlorites.

Chlorine preparation and properties, Group 17 P Block Elements 12

→ with hot and concentrated With hot and concentrated alkalies, chlorine forms chlorides and chlorates.

Chlorine preparation and properties, Group 17 P Block Elements 13

The above reaction is disproportionate reaction

Reaction with slaked lime: Chlorine reacts with it in two ways

→ With cold slaked lime, chlorine forms calcium hypochlorite Ca(OCl)2

Chlorine preparation and properties, Group 17 P Block Elements 14

→ With dry slaked lime, it produces bleaching power.

Chlorine preparation and properties, Group 17 P Block Elements 15

→ Reaction with hot and conc. slaked lime :

6Ca(OH)2 + 6Cl2 → 5CaCl2 + Ca(ClO3)2 + 6H2O

→ Reaction with hydrocarbons : Chlorine reacts with hydrocarbons. It show substitution reaction with saturated hydrocarbons and show addition reaction with unsaturated hydrocarbons.

Chlorine preparation and properties, Group 17 P Block Elements 16

→ Bleaching action : Chlorine can bleach natural colouring material like flowers creen leaves, indigo etc, in presence of water. The bleaching action of chlorine is due to its ability to oxidine coloured material into colourless material. The related reaction is as follows:

  • Cl2 + H2O → 2HCl + [O]
  • Coloured material + [O] → Colourless material

Chlorine preparation and properties, Group 17 P Block Elements

→ The bleaching action of chlorine is by oxidation hence it is permanent. Chlorine beaches only in presence of waterthus, dry chlorine cannot bleach dry flowers due to the absence of water. Its bleaching action is harmful because during bleaching hydrochloric acid (HCI) is formed thus, the deliente fibers are likely to be destroyed by HCI. That is why, chlorine la used only for bleaching wood palp, paper pulp and clothes etc.

→ Addition Reactions. Chlorine also show addition reactions

Chlorine preparation and properties, Group 17 P Block Elements 17

→ Reaction with other halogens: Chlorine can react with other halogen forming interhalogen compounds.

Chlorine preparation and properties, Group 17 P Block Elements 18

→ Reaction with non metals : Non metals like sulphur, phosphorus etc. can also react with chlorine.

Chlorine preparation and properties, Group 17 P Block Elements 19

→ Reaction with metalloids: Chlorine also recta with metalloids like As, Sh etc

Chlorine preparation and properties, Group 17 P Block Elements 20

→ Reaction with halides: Chlorine can replace less electronegative halogens from their halides

2KBr + Cl2 → 2KCl + Br2
2KI + Cl2 → 2KCl + I2

→ As oxidising agent : In presence of moisture chlorine behaves as strong oxidising agent. The yellow colour of chlorine is disappeared due to the formation of HCL and HOCl, HOCl form nascent oxygen which is responsible for the oxidising properties of chlorine.

Chlorine preparation and properties, Group 17 P Block Elements 21

→ Some important oxidising reactions of Cl2 are as follows:

Chlorine preparation and properties, Group 17 P Block Elements 22

→ In some reactions chlorine enn lo act as an oxidising agent in absence of water.

It oxidises ferrous chloride into ferric chloride.
Chlorine preparation and properties, Group 17 P Block Elements 23

Chlorine preparation and properties, Group 17 P Block Elements 24

Use of Chlorine

  • Used industrially for blenching wood pulp. It is also used in bleaching cotton, wood, textiles, paperete.
  • It is used in extraction of gold and platinum
  • It is used in manufacturing of dyes, drugs and organic compounds like CCl4 CHCl3, DDT, refrigerants etc.
  • It is used in manufacturing chlorates which are used in flashlight powder matches and explosive ete.
  • It is used in manufacturing the poisonous gases like phogene (COCl2), tear gas (CCl3NO2) and mustard gas (ClCH2CH2SCH2CH2Cl).
  • It is used in sterilising the drinking water
  • Used as germicides and insecticides

Chemistry Notes