Courses
Courses for Kids
Free study material
Offline Centres
More
Store Icon
Store

NCERT Solutions for Class 12 Chemistry Chapter 10 - Haloalkanes And Haloarenes

ffImage
Last updated date: 16th Apr 2024
Total views: 768.9k
Views today: 19.68k
MVSAT 2024

Download NCERT Solutions For Class 12 Chemistry Chapter 10 Free PDF

NCERT Solutions for Class 12 Chemistry Chapter 10 Haloalkanes and Haloarenes is available in PDF format, which can be downloaded through the direct link below. Students can refer to these solutions without any time constraints. The highly experienced faculty at Vedantu created the solutions based on the latest CBSE Syllabus and guidelines issued by the board. The exercise solutions help students understand the concepts covered in the chapter and improve their time management and problem-solving abilities. So, download the PDFand enhance your skills.


Don't Miss Out: Get Your Free JEE Main Rank Predictor 2024 Instantly!


Class:

NCERT Solutions for Class 12

Subject:

Class 12 Chemistry

Chapter Name:

Chapter 10 - Haloalkanes And Haloarenes

Content-Type:

Text, Videos, Images and PDF Format

Academic Year:

2024-25

Medium:

English and Hindi

Available Materials:

  • Chapter Wise

  • Exercise Wise

Other Materials

  • Important Questions

  • Revision Notes



Haloalkanes and Haloarenes Chapter at a Glance - Class 12 NCERT Solutions

  • Alkyl/ Aryl halides may be classified as mono, di, or polyhalogen (tri-, tetra-, etc.) compounds depending on whether they contain one, two or more halogen atoms in their structures.


  • Alkyl halides are prepared by the free radical halogenation of alkanes, addition of halogen acids to alkenes, replacement of –OH group of alcohols with halogens using phosphorus halides, thionyl chloride or halogen acids. Aryl halides are prepared by electrophilic substitution to arenes. Fluorides and iodides are best prepared by halogen exchange method.


  • The boiling points of organohalogen compounds are comparatively higher than the corresponding hydrocarbons because of strong dipole-dipole and van der Waals forces of attraction. These are slightly soluble in water but completely soluble in organic solvents.


  • The polarity of carbon-halogen bond of alkyl halides is responsible for their nucleophilic substitution, elimination and their reaction with metal atoms to form organometallic compounds.


  • Nucleophilic substitution reactions are categorised into SN1 and SN2 on the basis of their kinetic properties. SN2 reactions of chiral alkyl halides are characterised by the inversion of configuration while SN1 reactions are characterised by racemisation.


  • If the electron withdrawing group   NO2 is present at ortho- and para- positions than the reactivity of haloarenes is increased. -NO2 group shows its effect only at ortho- and para- positions but not at meta- position in the reactivity of haloarenes.


  • The electrophilic substitution reactions in haloarenes occur slowly and require more drastic conditions as com pared to those in benzene.


  • A number of polyhalogen compounds e.g., dichloromethane, chloroform, iodoform, carbon tetrachloride, freon and DDT have many industrial applications. However, some of these


  • compounds cannot be easily decomposed and even cause depletion of ozone layer and are proving environmental hazards.

Competitive Exams after 12th Science
More Free Study Material for Haloalkanes and Haloarenes
icons
Revision notes
694.8k views 11k downloads

Access NCERT Solution for Class 12 Chemistry Chapter 10 - Haloalkanes and Haloarenes

Intext Exercise

1. Write structures of the following compounds: 

  1. 2 - chloro-3methylpentane:

Ans: Main chain will be of five carbon atoms. At second position chlorine will be present and at third position, methyl group will be present.


2 - chloro-3methylpentane


  1. 1- chloro- 4 – ethylcyclohexane

Ans: A cyclic structure is present in which at 1st carbon there is chlorine present and at the 4th position ethyl group is present.


1- chloro- 4 – ethylcyclohexane


  1. 4 - tert .Butyl-3- iodoheptane

Ans: Main chain will be of seven carbon atoms. At 4th position tertiary butyl will be present and at the 3rd position iodine will be present.


4 - tert .Butyl-3- iodoheptane


  1. 1, 4 -Dibromobut- 2 – ene

Ans: Main chain will be of 4 carbon atoms and it is an alkene. There are two bromine atoms on the terminal carbon atoms.


1, 4 -Dibromobut- 2 – ene


  1. 1-Bromo- 4 - sec/ butyl- 2 -methylbenzene.

Ans: Main chain will be the benzene. Three substituents are present on benzene.


1-Bromo- 4 - sec/ butyl- 2 -methylbenzene.


2. Why is sulphuric acid not used during the reaction of alcohols with $\text{KI}$?

Ans: ${{\text{H}}_{\text{2}}}\text{S}{{\text{O}}_{\text{4}}}$ is a powerful oxidizer. $\text{HI}$generated during the reaction is oxidized, preventing the interaction between an alcohol and $\text{HI}$ from becoming alkyl iodide as a result of the process. ${{\text{H}}_{\text{3}}}\text{P}{{\text{O}}_{\text{3}}}$ is utilized as a non-oxidizing acid to prevent the oxidation of $\text{HI}$. The reaction is given below:

\[\text{2KI + }{{\text{H}}_{\text{2}}}\text{S}{{\text{O}}_{\text{4}}}\to \text{ 2KHS}{{\text{O}}_{\text{4}}}\text{+ 2HI }\to \text{ }{{\text{I}}_{\text{2}}}\] 


3. Write structures of different dihalogen derivatives of propane.

Ans: Propane is an alkane molecule containing three carbon atoms. Dihalogen derivatives are propane that includes two halogen atoms. There are four potential isomers. These are given below:

  1. 1,3-Dibromopropane


1,3-Dibromopropane


  1. 1,2-Dibromopropane


1,2-Dibromopropane


  1. 1,1-Dibromopropane


1,1-Dibromopropane


  1. 2,2-Dibromopropane


2,2-Dibromopropane


4. Among the isomeric alkanes of molecular formula ${{\text{C}}_{\text{5}}}{{\text{H}}_{\text{12}}}$ identify the one that one photochemical chlorination yields:

Ans: Isomeric alkane means that there will be different arrangements of substituents around the carbon atom. ${{\text{C}}_{\text{5}}}{{\text{H}}_{\text{12}}}$ is pentane and it is an alkane.

  1.  A Single Monochloride

Isomer of pentane that will yield single monochloride is neopentane and its structure is given below:


Structure of tert-pentane


Due to the fact that all of the H-atoms are identical, replacing any one of them will result in the same result.

  1.  Three isomeric monochlorides.

Isomer of pentane that will yield three isomeric monochlorides is n-pentane as given below:


Pentane


In this a, b, and c have three sets of equivalent hydrogen atoms.

  1.  Four isomeric monochlorides.

Isomer of pentane that will yield four isomeric monochlorides is iso-pentane which is given below:


Structure of isopentane


Because all the carbon atoms have different hydrogen atoms. 


5. Draw the structures of major monohalo products in each of the following reactions:



Complete the reaction


Ans: In this reaction the hydroxyl group will be replaced with the chlorine atom. The reaction is given below:

Halogenation of phenol



Complete the reaction


Ans: In this reaction the amine group will be replaced with methyl bromide. The reaction is given below:


Halogenation of nitro benzyl amine




complete the reaction


Ans: In this reaction the hydroxyl group with the methyl group will be replaced with the chlorine atom. The reaction is given below:


Replacement of hydroxyl group with chloride




Complete the reaction


Ans: In this reaction the iodine from the hydrogen iodide will attach the carbon atom having the double bond as well as methyl group. The reaction is given below:


Addition of ido group to cycloalkene


  1. $\text{C}{{\text{H}}_{\text{3}}}\text{C}{{\text{H}}_{\text{2}}}\text{Br+NaI}\to $ 

Ans: In this reaction the iodine atom will replace the bromine in the haloalkane. The reaction is given below:

\[\text{C}{{\text{H}}_{\text{3}}}\text{C}{{\text{H}}_{\text{2}}}\text{Br + NaI }\to \text{ C}{{\text{H}}_{\text{3}}}\text{C}{{\text{H}}_{\text{2}}}\text{I + NaBr}\]



complete the reaction


Ans: In this reaction, the bromine atom will attack the alpha-carbon atom of the double bond. The reaction is given below:

Halogenation by Substitution reaction
    


6. Arrange each set of compounds in order of increasing boiling points.

  1. Bromomethane, Bromoform, Chloromethane, Dibromomethane.

Ans: As we can see that all the compounds given above are haloalkanes. The order will be:

Chloromethane < Bromomethane < Dibromomethane < Bromoform

This is due to the fact that as the halogen size increases the boiling point will increase and as the number of halogen atoms increases in the same chain, the boiling point will increase.

  1. Chloropropane, Isopropyl chloride, 1 -Chlorobutane. 

Ans: In all the compounds there is chlorine atom present and the size of the alkyl chain is different. The order will be:

Isopropyl chloride < 1- Chloropropane < 1 – Chlorobutane 

This is due to the fact that as the branching of the chain increases the boiling point will decrease and as the size of the chain increases the boiling point will increase.


7. Which alkyl halide from the following pairs would you expect to react more rapidly by an ${{\text{S}}_{\text{N}}}\text{2}$ mechanism?  Explain your answer?

Ans: For the ${{\text{S}}_{\text{N}}}\text{2}$ reaction the order of reactivity is ${{1}^{\circ }}>{{2}^{\circ }}>{{3}^{\circ }}$, so we can solve the question according to the order of the reactivity. 

  1. $\text{C}{{\text{H}}_{\text{3}}}\text{C}{{\text{H}}_{\text{2}}}\text{C}{{\text{H}}_{\text{2}}}\text{C}{{\text{H}}_{\text{2}}}\text{Br}$ or 


(image will be uploaded soon)  

Ans: In the first compound the alkyl halide is primary halide while the second compound is a secondary halide. So, the first compound will react more rapidly.


Secondary halide and tertiary halide


Ans: In the first compound the alkyl halide is secondary halide while the second compound is a tertiary halide. So, the first compound will react more rapidly.


3-methylbromopentane and 2-methylbromopentane



Ans: Both compounds are secondary halides but the steric hindrance by the $\text{C}{{\text{H}}_{\text{3}}}$ group will have more effect in the second compound so, the first compound will react more rapidly.


8. In the following pairs of halogen compounds, which compound undergoes faster ${{\text{S}}_{\text{N}}}\text{1}$  reaction?

Ans: For the ${{\text{S}}_{\text{N}}}1$reaction the order of reactivity is ${{3}^{\circ }}>{{2}^{\circ }}>{{1}^{\circ }}$, so we can solve the question according to the order of the reactivity.


Tertiary and secondary haloalkane

Ans: The first compound is tertiary compound and the second compound is secondary compound. So, the first compound will undergo a faster ${{\text{S}}_{\text{N}}}1$reaction.



Primary and secondary haloalkane


Ans: The first compound is a secondary compound and the second compound is primary compound. So, the first compound will undergo a faster ${{\text{S}}_{\text{N}}}1$reaction.


9. Identify A, B, C, D, E, R and ${{\text{R}}^{\text{1}}}$ in the following:


The compound A in the reaction is cyclohexylmagnesium bromide, compound B is Cyclohexane


Ans: The compound A in the reaction is cyclohexylmagnesium bromide, compound B is Cyclohexane. 

Compound R –Br will be 2-Bromopropane and the compound C is given below:


Grignard Reagent


The third part of the question is incorrect because the tertiary-alkyl halides do not undergo wurtz reaction but they undergo dehydrohalogenation to give alkenes. 

So, the compound ${{\text{R}}^{\text{1}}}\text{-Br}$ is given below:


Isopropane


Compound D is Tertiary butyl magnesium bromide and compound E is 2-Methylpropane.

The complete reaction is given below:


Complete reaction


NCERT Exercise

1. Name the following halides according to IUPAC system and classify them as alkyl, benzyl (primary, secondary, tertiary), vinyl or aryl halides:

  1. ${{\text{(C}{{\text{H}}_{\text{3}}}\text{)}}_{\text{2}}}\text{CHCH(Cl)C}{{\text{H}}_{\text{3}}}$ 

Ans: The name of the compound is 2-Chloro-3-methyl butane and it is a secondary alkyl halide.

  1. $\text{C}{{\text{H}}_{\text{3}}}\text{C}{{\text{H}}_{\text{2}}}\text{CH(C}{{\text{H}}_{\text{3}}}\text{)CH(}{{\text{C}}_{\text{2}}}{{\text{H}}_{\text{5}}}\text{)Cl}$

Ans: The name of the compound is 3-Chloro-4-methyl hexane and it is a secondary alkyl halide.

  1. $\text{C}{{\text{H}}_{\text{3}}}\text{C}{{\text{H}}_{\text{2}}}\text{C(C}{{\text{H}}_{\text{3}}}{{\text{)}}_{\text{2}}}\text{C}{{\text{H}}_{\text{2}}}\text{I}$ 

Ans: The name of the compound is 1-Iodo-2,2-dimethyl butane and it is a primary alkyl halide.

  1. ${{\text{(C}{{\text{H}}_{\text{3}}}\text{)}}_{\text{3}}}\text{CC}{{\text{H}}_{\text{2}}}\text{CH(Br)}{{\text{C}}_{\text{6}}}{{\text{H}}_{\text{5}}}$ 

Ans: The name of the compound is 1-Bromo-3,3-dimethyl-1-phenylbutane and it is a secondary benzylic halide.

  1. $\text{C}{{\text{H}}_{\text{3}}}\text{CH(C}{{\text{H}}_{\text{3}}}\text{)CH(Br)C}{{\text{H}}_{\text{3}}}$ 

Ans: The name of the compound is 2-bromo-3-methyl butane and it is a secondary alkyl halide.

  1. $\text{C}{{\text{H}}_{\text{3}}}\text{C(}{{\text{C}}_{\text{2}}}{{\text{H}}_{\text{5}}}{{\text{)}}_{\text{2}}}\text{C}{{\text{H}}_{\text{2}}}\text{C}{{\text{H}}_{\text{3}}}$ 

Ans: The name of the compound is 1-bromo-2-ethyl-2-methyl butane and it is a primary alkyl halide.

  1. $\text{C}{{\text{H}}_{\text{3}}}\text{C(Cl)(}{{\text{C}}_{\text{2}}}{{\text{H}}_{\text{5}}}\text{)C}{{\text{H}}_{\text{2}}}\text{C}{{\text{H}}_{\text{3}}}$ 

Ans: The name of the compound is 3-Chloro-3-methyl pentane and it is a tertiary alkyl halide.

  1. $\text{C}{{\text{H}}_{\text{3}}}\text{CH=C(Cl)C}{{\text{H}}_{\text{2}}}\text{CH(C}{{\text{H}}_{\text{3}}}{{\text{)}}_{\text{2}}}$ 

Ans: The name of the compound is 3-Chloro-5-methyl hex-2-ene and it is a vinylic halide.

  1. $\text{C}{{\text{H}}_{\text{3}}}\text{CH=CHC(Br)(C}{{\text{H}}_{\text{3}}}{{\text{)}}_{\text{2}}}$ 

Ans: The name of the compound is 4-bromo-4-methyl pent-2-ene and it is allylic halide.

  1. $\text{p-Cl}{{\text{C}}_{\text{6}}}{{\text{H}}_{\text{4}}}\text{C}{{\text{H}}_{\text{2}}}\text{C(C}{{\text{H}}_{\text{3}}}{{\text{)}}_{\text{2}}}$ 

Ans: The name of the compound is 1-Chloro-4-(2-methylpropyl) benzene and it is an aryl halide.

  1. $\text{m-ClC}{{\text{H}}_{\text{2}}}{{\text{C}}_{\text{6}}}{{\text{H}}_{\text{4}}}\text{C}{{\text{H}}_{\text{2}}}\text{C(C}{{\text{H}}_{\text{3}}}{{\text{)}}_{\text{3}}}$ 

Ans: The name of the compound is 1-Chloromethyl-3-(2,2-dimethylpropyl) benzene and it is a primary benzylic halide.

  1. $\text{o-Br-}{{\text{C}}_{\text{6}}}{{\text{H}}_{\text{4}}}\text{CH(C}{{\text{H}}_{\text{3}}}\text{)C}{{\text{H}}_{\text{2}}}\text{C}{{\text{H}}_{\text{3}}}$ 

Ans: The name of the compound is 1-Bromo-2-(1-methylpropyl) benzene and it is an aryl halide.


2. Give the IUPAC names of the following compounds: 

(i)CH3CH(Cl)CH(Br)CH3 

Ans: The IUPAC name of this compound is 2-Bromo-3-chlorobutane. 

(ii)CHF2CBrClF 

Ans: The IUPAC name of this compound is 1-Bromo-1-chloro-1, 2, 2- trifluoroethane. 

(iii)ClH2C≡CCH2Br  

Ans: The IUPAC name of this compound is 1-Bromo-4-chlorbut-2-yne. 

(iv)(CCl 3 ) 3 CCl 

Ans: The IUPAC name of this compound is 2-(Trichloromethyl)- 1, 1, 1, 2, 3, 3, 3- heptachloropropane. 

(v)CH3C(p-ClC6H4 )2 CH 3 

Ans: The IUPAC name of this compound is 2-Bromo-3, 3-bis-(4-chlorophenyl)  butane. 

(vi)(CH3 )3CCH=C(Cl)C6 H4 I-p 

Ans: The IUPAC name of this compound is 1-Chlor-1-(4-iodophenyl)-3, 3- dimethylbut-1-ene. 


3. Write the structures of the following organic halogen compounds: 

(i) 2-Chloro-3-methylpentane

Ans: The structure of this compound will be: 

(ii) p-Bromochlorobenzene 

Ans: The structure of this compound will be: 

(image will be uploaded soon)

(iii) l-Chloro-4-ethylcyclohexane 

Ans: The structure of the compound will be: 

(image will be uploaded soon)

(iv)2- (2-Chlorophenyl) -1- iodooctane 

Ans: The structure of the compound will be: 

(image will be uploaded soon)

(v) 2-Bromobutane 

Ans: The structure of the compound will be: 

(image will be uploaded soon)

(vi) 4-tert-Butyl-3-iodoheptane 

Ans: The structure of the compound will be:

(image will be uploaded soon)

(vii) 1-Bromo-4-sec-butyl-2-methylbenzene 

Ans: The structure of the compound will be: 

(image will be uploaded soon)

(viii) l, 4-Dibromobut-2-ene 

Ans: The structure of the compound will be: 

BrCH2 -CH=CH-CH2 Br


4. Which one of the following has the highest dipole moment?  CH2Cl2, CHCl3 or CCl4 

Ans: Below are the three-dimensional structures of the three compounds, as well as the  direction of each bond's dipole moment: 

(image will be uploaded soon)

CCl4has no dipole moment since it is symmetrical. When two C-Cl dipole moments  are added to CHCl3, the C-H and C-Cl bonds oppose each other. CHCl3has a limited dipole moment (1.03 D) because the dipole moment of the second resultant is  anticipated to be less than that of the first. This means that in CH2Cl2, the resulting  dipole moment of C-Cl pairs is greater than in CHCl3. Due to its dipole moment,  CH2 Cl2  is the strongest. 


5. A hydrocarbon C5H10does not react with chlorine in dark but gives a single  monochloro compound C5H9Cl in bright sunlight. Identify the hydrocarbon.

Ans: The molecular formula of the hydrocarbon might be either cycloalkane or alkene.  Since the molecule does not react with Cl2in the dark, it must be a cycloalkane. Since  the cycloalkane interacts with Cl2in the presence of strong sunshine to form a single  monochloro compound, C5H9Cl, all ten hydrogen atoms in the cycloalkanes must be  equivalent. Thus, cyclopentane is the cycloalkane. 

(image will be uploaded soon)


6. Write the isomers of the compound having formula C4H9Br. 

Ans: First we have find the Double bond equivalent (DBE) for C4H9Br. It is given  below: 

$\frac{4(4-2)+9(1-2)+1(1-2)}{2}+1=0$ 

The answer is zero which means that there is no ring or unsaturation in the isomers of  the given compound, all the isomers will be either branched or straight chain. So, there  will be four isomers and these are given below: 

(i)1- Bromobutane: 

(image will be uploaded soon)

CH3CH2CH2CH2Br

(ii) 1-Bromo-2-Methylpropane:

(image will be uploaded soon)

(iii)2-Bromo Butane: 

(image will be uploaded soon)

(iv)2-Bromo-2-Methylpropane: 

(image will be uploaded soon)


7. Write the equation for the preparation of 1-iodobutane from:

 (i)1-Butanol 

Ans: 1-Butanol will react with potassium iodide and phosphoric acid to form the 1- Iodobutane. The reaction is given below: 

$CH_3CH_2CH_2CH_2OH+KI+H_3PO_4 \rightarrow CH_3CH_2CH_2CH_2I+H_2O+KH_2PO_4$

(ii) 1-Chlorobutane 

Ans: 1-Chlorobutane will react with potassium iodide in the presence of acetone to  form the 1-Iodobutane. The reaction is given below: 

$CH_3CH_2CH_2CH_2Cl + KI \overset{Acetone}\rightarrow CH_3CH_2CH_2CH_2I + KCI$

(iii)But-1-ene 

Ans: But-1-ene will react with hydrogen bromide in the presence of peroxide to give  1-Bromobutane and then it reacts with sodium iodide in the presence of acetone to give  1-Iodobutane. The reaction is given below: 

$CH_3CH_2-CH+HBr\overset{Acetone}{\rightarrow}CH_3CH_2CH_2CH_2I+KCI$


8. What are ambident nucleophiles? Explain with an example. 

Ans: Ambident nucleophiles are nucleophiles that can attack at two distinct locations.  It is a resonance hybrid of the following two structures (for example, the cyanide  ion).Cyanide ion is a resonance hybrid of the following two structures: 

$\colon \overset{\mathbf-}C\equiv N\colon\longleftrightarrow\colon C =  \overset{\mathbf-}N:$

It may attack carbon to produce cyanide, and nitrogen to form isocyanide, depending  on the chemical. 


9. Which compound in each of the following pairs will react faster in $S_n 2$ reaction  with - OH? 

(i)CH3 Br or CH3

Ans: Both the compounds are alkyl halide but the iodide ion is a larger atom than  bromide ion. So, -Iion is better leaving group than - Brion. Therefore, CH I3will react  faster than CH 3 Br towards $S_n 2$ reaction with hydroxyl ion. 

(ii) (CH3  )3  CCl or CH 3  Cl  

Ans: In SN2 reaction the steric hindrance should be very less. (CH3)3 CClhas very  high steric hindrance and CH3Cl has less steric hindrance. So, CH3Cl will react faster  to the SN 2reaction with hydroxyl ion. 


10. Predict all the alkenes that would be formed by dehydrohalogenation of the  following halides with sodium ethoxide in ethanol and identify the major  alkene: 

(i) 1-Bromo-1-methylcyclohexane 

Ans: The major product when 1-Bromo-1-methylcyclohexane reacts with sodium  ethoxide in ethanol will give 1-Methylcyclohexene. The reaction is given below: 

(image will be uploaded soon)

(ii) 2-Chloro-2-methylbutane.

Ans: 2-Chloro-2-methyl butane has two different sets of equivalent beta-hydrogen and  hence, in principle, can give two alkenes. But according to Satzeff’s rule, more highly  substituted alkene is more stable and is the major product. The reaction is given below: 

(image will be uploaded soon)

(iii) 2, 2, 3-Trimethyl-3-bromopentane. 

Ans: 2, 2, 3-Triethyl-3-bromopentane has two different sets of equivalent beta hydrogen and hence, in principle, can give two alkenes. But according to Satzeff’s rule,  more highly substituted alkene is more stable and is the major product. The reaction is  given below: 

(image will be uploaded soon)


11. How will you bring about the following conversions? 

(i) Ethanol to but-1-yne. 

Ans: Ethanol will react with SOCl2and pyridine to Chloroethane. Acetylene will react  with NaNH2to form sodium acetylide. Now Chloroethane and Sodium acetylide will  react to form But-1-yne. The reactions are given below:

$CH_3CH_20H\overset{SOCl_2,Pyridine }{\rightarrow}CH_3CH_2-CI$

$CH \equiv CH + NaNH_2 \overset{Liq. NH , 196K }{\rightarrow}HC \equiv C^{-}NA^+4$

$CH_3CH_2CI + HC \equiv C^- Na^+\rightarrow CH_3CH_2-C \equiv CH +NaCI$

(ii) Ethane to bromoethene 

Ans: Ethane will react with bromine to form bromoethane. Now, this bromoethane will  react with KOH to form ethene and then there will be the formation of 1, 2- Dibromoethane. Now, 1, 2-Dibromoethane will react with alcoholic KOH to form  Bromoethene. The reactions are given below: 

$CH_3-CH_3 + Br_2 \overset{hv, 520-670K }{\rightarrow}CH_3CH_2 Br\overset{ KOH(alc.) }{\rightarrow}CH_2=CH_2$

$CH_2=CH_2 \overset{Br_2/CCI_4 }{\rightarrow}Br CH_2=CH_2 Br \overset{KOH(alc.)}{\rightarrow}CH_2= CHBr$

(iii) Propene to 1-Nitropropane 

Ans: Propene will react with Hydrogen bromide in peroxide effect to form 1- Bromopropane. Now, 1-Bromopropane will react with silver nitrite to given 1- Nitropropane. The reaction is given below: 

$CH_3-CH=CH_2 \overset{HBr}{\rightarrow}CH_3CH_2CH_2Br \overset{AgNO_2}{\rightarrow}CH_3CH_2CH_2NO_2$

(iv)Toluene to benzyl alcohol 

Ans: Toluene will react with chlorine in the presence of light to give benzyl chloride  and this benzyl chloride will react with aqueous KOH to give benzyl alcohol. The  reaction is given below: 

(image will be uploaded soon)

(v) Propene to propyne 

Ans: Propene will react with bromine in the presence of carbon tetrachloride to give 1,  2-Dibromopropane. Now, 1, 2-Dibromopropane will react with NaNH2and liquid  ammonia to give propyne. The reaction is given below:

(image will be uploaded soon)

(vi)Ethanol to ethyl Fluoride 

Ans: Ethanol will react with SOCl2and pyridine to form ethyl chloride. Now, ethyl  chloride will react with Hg F2 2to form Ethyl fluoride. The reaction is given below: 

$CH_3CH_2OH \overset{SOCI_2, Pyridine} \rightarrow CH_3CH_2-CI \overset{Hg_2F_2} \rightarrow CH_3CH_2-F$

(vii) Bromomethane to Propanone 

Ans: Bromomethane will react with KCN in the presence of ethanol to form  acetonitrile. Acetonitrile will react with CH MgBr 3in the presence of ether and then  with water to give Propanone. The reaction is given below: 

(image will be uploaded soon)

(viii) But-1-ene to but-2-ene 

Ans: But-1-ene will react with Hydrogen bromide to form 2-Bromobutane and this will  react with alcoholic KOH to form But-2-ene. The reaction is given below: 

(image will be uploaded soon)

(ix)1-Chlorobutane to n-octane

Ans: 1-Chlorobutane will react with sodium and dry ether to form n-octane. The  reaction is given below: 

$2CH_3CH_2CH_2CH_2Cl + 2Na \overset{Dry\, \,  etere}\rightarrow CH_3(CH_2)_6CH_3 + 2Nacl$

(x) Benzene to biphenyl 

Ans:Benzene will react with Bromine in the presence of FeBr3to form Bromobenzene.  Bromobenzene will react with sodium to form Biphenyl. The reaction is given below: 

(image will be uploaded soon)


12. Explain why 

(i)The dipole moment of chlorobenzene is lower than that of cyclohexyl chloride? 

Ans: S-character increases electronegative properties of chlorobenzene 2 

sp -hybrid  

carbon. Because of this, the chlorobenzene C atom is less likely than the cyclohexyl  chloride C atom to release electrons to Cl. C-Cllink in chlorobenzene is hence less  polar than cyclohexyl chloride. In addition, the C-Clbond in chlorobenzene has a  double bond character due to the delocalization of Cl's lone electron pairs across the  benzene ring as opposed to cyclohexyl chloride, which has a pure single bond. Or to  put it another way, the chlorobenzene C-Clbond is shorter than that of the cyclohexyl  chloride. Considering that the dipole moment is a function of charge and distance.  C-Cldistance is shorter in chlorobenzene, therefore it has a smaller dipole moment  than cyclohexyl chloride. 

(ii) Alkyl halides, though polar, are immiscible with water? 

Ans: Dipole-dipole attraction holds alkyl halides together. 

H-bonds hold the molecules of HO2 together. Alkyl halides are not soluble in water  because the new forces of attraction between water and alkyl halide molecules are  lower than the existing forces of attraction between alkyl halide - alkyl halide  molecules and water-water molecules. 

In addition, alkyl halides are unable to establish hydrogen bonds with water or to  disrupt the H-bonding network that exists in water. 

(iii)Grignard reagents should be prepared under anhydrous conditions? 

Ans: The reactivity of the Grignard reagent is very high. When they come in contact with water they readily react and form alkanes. The general reaction is given below:

R-Mg-X + H-OH→  R-H + Mg(OH)X 

Therefore, the Grignard reagent should be made in anhydrous condition. 


13. Give the uses of Freon-12, DDT, carbon tetrachloride and iodoform. 

Ans:  

Iodoform:  

Early on it was considered to be an antiseptic, however the characteristics are  attributable to the free iodine that is released, not the substance itself. It has been  superseded by other iodine-containing formulations due to its offensive odour. 

Carbon Tetrachloride: 

For oil, fats, and resins in the industrial sector, as well as in dry cleaning. In addition, CCl4vapours are extremely inflammable, according to the manufacturer.  As a result, CCl4is sold as pyrene, a fire extinguishing agent. 

Used in the production of aerosol can refrigerants and propellants. 

Freons:  

Industry uses Freon-12 (CCl F2 2), which is the most prevalent form of refrigerant. Refrigerant or air-conditioning components, aerosol propellants 

DDT: 

Its efficacy against mosquitoes that carry malaria and other insects that harm crops led  to a dramatic increase in its usage worldwide following World War II. DDT, on the other hand, has been widely used since the 1940s. Toxic for fishes, DDT  acquired tolerance in many insect species. When it comes to animals, DDT is not  readily metabolised, but instead accumulates and is retained in fatty tissues. As long as  the animals continue to eat DDT at the same rate, it builds up in their bodies. 


14. Write the structure of the major organic product in each of the following  reactions: 

(i)$\mathbf{CH_3CH_2CH_2Cl +NaI \overset{Acetone, Heat}\rightarrow} $ 

Ans: The Chlorine atom from the alkyl halide by iodine. The major product of the  reaction is 1-Iodopropane. The reaction is given below: 

$CH_3CH_2CH_2Cl + NaI \overset{Acetone, Heat}\rightarrow CH_3CH_2CH_2 I + NaCl$

(ii)$\mathbf{(CH_3)_3CBr + KOH \overset{Ethanol}\rightarrow }$ 

Ans: There will be Dehydrohalogenation and the major product of the reaction is 2- methylpropene. The reaction is given below: 

(image will be uploaded soon)

(iii)$\mathbf{C_3CH(Br)CH_2CH_3 + NaOH \overset{water}\rightarrow }$

Ans: The bromine atom will be replaced with the hydroxyl ion. The major product will  be Butan-2-ol. The reaction is given below:

 (image will be uploaded soon)

(iv)$\mathbf{CH_3CH_2Br +KCN \overset{aq.ethanol } \rightarrow} $

Ans: The bromide ion will be replaced with the cyanide ion. The major product will  be propanenitrile. The reaction is given below: 

$CH_3CH_2Br +KCN \overset{aq.ethanol } \rightarrow CH_3CH_2CN + KBr$

(v)$\mathbf{C_6H_5ONa + C_2H_5Cl \rightarrow} $

Ans: The major product in the above reaction will be Phenetole. The reaction is given  below: 

$C_6H_5ONa + C_2H_5Cl \rightarrow C_6H_5-O-C_2H_5+ NaCl $

(vi)CH3CH2CH2OH + SOCl2 → 

Ans: The hydroxyl ion in the alkyl halide will be replaced with chloride ion. The major  product of the reaction will be 1-Chloropropane. The reaction is given below: 

CH3CH 2CH2OH + SOCl2 → CH3 CH2CH2Cl + SO2 + HCl

(vii)$\mathbf{CH_3CH_2CH=CH_2+HBr \overset{peroxide}\rightarrow} $

Ans: Since peroxide is used in the reaction, there will be Anti-Markovnikov's addition.  The major product in the reaction will be 1-Bromobutane. The reaction is given below: 

$CH_3CH_2CH=CH_2+HBr \overset{peroxide}\rightarrow CH_3CH_2CH_2CH_2Br$

(viii)CH3CH=C(CH3)2 + HBr → 

Ans: In this reaction there will be Markovnikoff’s addition. The major product of the  reaction will be 2-Bromo-2-methylbutane. The reaction is given below: 

(image will be uploaded son)


15. Write the mechanism of the following reaction: 

$\mathbf{n-BuBr + KCN \overset{EtoH-H_2O}\rightarrow n BuCN}$

Ans: There are two contributing resonance hybrid structures of KCN due the  cyanide ion present. It is given below: 

$K^{+}[-: C=N:\leftrightarrow :C=N:-]$

So, as we can see that the - CNion is an ambident nucleophile. Therefore, it can attack  from either C atom or from N atom towards n-BuBr. The strength of C-C bond is  stronger than C-N bond, therefore, the attack will take place from C atom towards n Butyl bromide to form n-butyl cyanide. The reaction is given below: 

(image will be uploaded soon)


16. Arrange the compounds of each set in order of reactivity towards SN2 displacement: 

Ans: For the SN2 reaction the order of reactivity is 1 2 3 > >, so we can solve the  question according to the order of the reactivity. 

(i)2-Bromo-2-Methylbutane, 1-Bromopentane, 2-Bromopentane. 

First let us draw all the structures of the compound. 

2-Bromo-2-Methyl butane:

(image will be uploaded soon)

1-Bromopentane: 

CH CH CH CH CH -Br 3 2 2 2 2 

2-Bromopentane: 

(image will be uploaded soon)

The order will be: 

1-Bromopentane > 2-Bromopentane > 2-Bromo-2-methyl butane. 

(ii) 1-Bromo-3-methylbutane,2-Bromo-2-methylbutane,3-Bromo-2- methylbutane 

Ans: The structures of the compounds are given below: 

(image will be uploaded soon)

1-Bromo-3-methylbutane: 

2-Bromo-2-methylbutane: 

(image will be uploaded soon)

3-Bromo-2-methylbutane: 

(image will be uploaded soon)

The order of the reactivity will be: 

1-Bromo-3-methylbutane > 3-Bromo-2-methylbutane > 2-Bromo-2-methyl butane. 

(iii)1-Bromobutane, 1-Bromo-2,2-dimethypropane, 1-Bromo-2-methylbutane, 1- Bromo-3-methyl butane.

Ans: The structure of the compounds are given below: 

(image will be uploaded soon)

1-Bromobutane: 

CH3 CH2  CH2 CH2 Br

1-Bromo-2, 2-dimethylpropane: 

(image will be uploaded soon)

1-Bromo-2-methylbutane: 

(image will be uploaded soon)

1-Bromo-3-methylbutane: 

(image will be uploaded soon)

The order of reactivity will be: 

1-Bromobutane > 1-Bromo-3-methylbutane > 1-Bromo-2-methylbutane > 1-Bromo-2,  2-dimethylpropane. 

This is decided by the fact that steric hindrance should be less for S 2Nfor the  reactivity. 


17. Out of C6 H5CH2Cl and C6H5CHClC6H5 which is more easily hydrolyzed by  aqueous KOH. 

Ans: C6H5CHCl2 is a primary aryl halide but C6H5CHClC6H5 is a secondary aryl  halide. If reaction with aqueous KOH is a SN1 reaction then it is based on the stability  of the carbocation. The formation of carbocation is given below:

(image will be uploaded soon)

Secondary carbocation is more stable than primary carbocation so, the  C6H5CHClC6H5  will react faster. 

But if the reaction is SN2 then C6H5CHCl2 will react faster because the reactivity is  of opposite order. 


18. p-Dichlorobenzene has higher m.p. and lower solubility than those of o-and  m-isomers. Discuss.  

Ans: There are greater molecular forces of attraction between p-isomers and o-isomers  due to it being more symmetrical and fitting into the crystal lattice more tightly. Due  to the fact that the crystal lattice breaks during melting or dissolution, a greater amount  of energy is required to melt or dissolve the p-isomer than the o- and m-isomers. This  means that p-isomers have higher melting points and lower solubilities than their  equivalent o- and m-isomers. 


19. How the following conversions can be carried out: 

(i)Propene to propan-1-ol 

Ans: Propene will react with hydrogen bromide in the presence of peroxide to give 1- Bromopropane. Now, this 1-Bromopropane will react with aqueous KOH to form  Propan-1-ol. The reaction is given below: 

$CH_3CH=CH_2\overset{HBr/ peroxide}\rightarrow CH_3CH_2CH_2Br\overset{Aq. KOH}\rightarrow CH_3CH_2CH_2OH$

(ii) Ethanol to but-2yne 

Ans: Ethanol will react with iodine and phosphorus to form Iodoethane then it will  convert to ethene. Now ethene will react with bromine in the presence of carbon  tetrachloride to form1, 2-Dibromoethane, this on dehydrohalogenation and reaction 

(image will be uploaded soon)

with NaNH2will form disodium acetylide. Later this reaction with methyl iodide will  give But-2-yne. The reaction is given below: 

(iii)1-Bromopropane to 2-bromopropane 

Ans: 1-Bromopropane will react with alcoholic KOH to form propene. Propene will  react with HBr to form 2-Bromopropane. The reaction is given below: 

$CH_3CH_2CH_2Br\overset{Alc.KOH}\rightarrow CH_3CH=CH_2 \overset{HBr}\rightarrow CH_3-CH(Br)-CH_3$

(iv)Toluene to Benzyl alcohol. 

Ans: Toluene will react with chlorine in the presence of light to give benzyl chloride  and this benzyl chloride will react with aqueous KOH to give benzyl alcohol. The  reaction is given below: 

(image will be uploaded soon)

(v) Benzene to 4-bromonitrobenzene

Ans: Benzene will react with Bromine in the presence of FeBr3to form  Bromobenzene. Bromobenzen will react with concentrated nitric acid and concentrated  sulfuric acid to form 4-Bromonitrobenzene. The reaction is given below: 

(image will be uploaded soon)

(vi) Benzyl alcohol to 2-phenylethanoic acid 

Ans: Benzyl alcohol will react with SOCl2to form Benzyl chloride. Benzyl chloride  will react with KCN to form Benzyl cyanide. Now, benzyl cyanide on hydrolysis will  give 2-Phenylethanoic acid. The reaction is given below: 

(image will be uploaded soon)

(vii) Ethanol to Propanenitrile 

Ans: Ethanol will react with iodine in the presence of phosphorus to form Iodoethane.  Iodoethane will react with KCN in the presence of aqueous ethanol to give  Propanenitrile. The reaction is given below: 

$CH_3CH_2OH \overset{p/I_2}\rightarrow CH_3CH_2I  \overset{KCN/aq.Ethanol}\rightarrow CH_3CH_2CN$

(viii)Aniline to Chlorobenzene

Ans: Aniline will undergo diazotization to form Benzene diazonium chloride. The  Benzene diazonium chloride will react with copper chloride in the presence of  hydrochloric acid to give Chlorobenzene. The reaction is given below: 

(image will be uploaded soon)

(ix)2-Chlorobutane to 3, 4-Dimethylhexane 

Ans: 2-Chlorobutane will react with sodium in the presence of dry ether to form 3, 4- Dimethylhexane. The reaction is given below:

(image will be uploaded soon) 

(x) 2-Methyl-1-propene to 2-Chloro-2-methylpropane 

Ans: 2-Methyl-1-propene will react with Hydrogen chloride to give 2-Chloro-2- methylpropane. The reaction is given below: 

(image will be uploaded soon)

(xi) Ethyl chloride to propanoic acid 

Ans: Ethyl chloride will react with KCN to give propanenitrile. Propanenitrile on  hydrolysis will give propanoic acid. The reaction is given below: 

$CH_3CH_2Cl \overset{KCN}\rightarrow CH_3CH_2CN \overset{H^{+}/H_2O}\rightarrow CH_3CH_2COOH$

(xii) But-1-ene to n-butyl iodide 

Ans: But-1-ene will react with HBr in the presence of peroxide to form 1- Bromobutane. 1-Bromobutane will react with NaI in the presence of Acetone to give  n-butyl iodide. The reaction is given below:

$CH_3CH_2CH=CH_2 \xrightarrow[peroxide]{HBr}CH_3CH_2CH_2CH_2Br \xrightarrow[Acetone]{Nal} CH_3CH_2CH_2CH_2I$

(xiii)2-Chloropropane to 1-propanol 

Ans: 2-Chloropropane will undergo dehydrohalogenation to give propene. Propene  will react with HBr in the presence of peroxide to give 1-bromopropane. 1- Bromopropane will react with KOH to form 1-Propanol. The reaction is given below: 

(image will be uploaded soon)

(xiv)Isopropyl alcohol to Iodoform 

Ans: Isopropyl alcohol will react with iodine and sodium hydroxide to give Iodoform.  The reaction is given below: 

(image will be uploaded soon)

(xv) Chlorobenzene to p-nitrophenol 

Ans: Chlorobenzene will react with concentrated nitric acid and concentrated sulfuric  to give p-Chloronitrobenzene. p-Chloronitrobenzene will react with 15% sodium  hydroxide and hydrochloric acid to give p-nitrophenol. The reaction is given below:

(image will be uploaded soon)

(xvi)2-Bromopropane to 1-bromopropane 

Ans: 2-Bromopropane will react with alcoholic KOH to form Propene. Now, propene  will react with HBr in the presence of peroxide to form 1-Bromopropane. The reaction  is given below: 

(image will be uploaded soon)

(xvii) Chloroethane to butane 

Ans: Chloroethane will react with sodium in the presence of butane. The reaction is  given below: 

$2CH_3CH_2-Cl + 2Na \overset{ Dryethere}\rightarrow CH_3CH_2CH_2CH_3 + 2NaCl$

(xviii) Benzene to diphenyl 

Ans: Benzene will react with Bromine in the presence of FeBr3to form Bromobenzene.  Bromobenzene will react with sodium to form Biphenyl. The reaction is given below: 

(image will be uploaded soon)

(xix)Tert-Butyl bromide to isobutyl bromide 

Ans: Tert-butyl bromide will react with alcoholic KOH to form 2-Methyl-1-propene.  2-Methyl-1-propene will react with HBr in the presence of peroxide to form isobutyl  bromide. The reaction is given below: 

(image will be uploaded soon)

(xx) Aniline to phenylisocyanide 

Ans: Aniline will react with chloroform and alcoholic KOH to form Phenyl isocyanide.  The reaction is given below:

(image will be uploaded soon)


20. The treatment of alkyl chlorides with aqueous KOH leads to the formation of  alcohols but in the presence of alcoholic KOH, alkenes are major products.  Explain. 

Ans: Because of its high nucleophilicity, KOH is nearly fully deionized in water to  generate - OHions, which then undergo substitution reactions with alkyl halides to  form alcohols. 

OH- ions are strongly solvated in the aqueous solution (hydrated). A result of this  process is that alkyl chloride fails to extract a hydrogen from its p-carbon in order to  create alkenes. While an alcohol-based solution of KOH contains an ion known as the  alkoxide (- RO), this strong base preferentially removes HCI from an alkyl chloride to  produce alkenes. 


21. Primary alkyl halide C4H9Br(a) reacted with alcoholic KOH to give  compound (b) Compound (b) is reacted, with HBr to give (c) which is an  isomer of (a). When (a) is reacted with sodium metal it give compound (d),  C8 H18which is different from the compound formed when n-butyl bromide is  reacted with sodium. Give the structural formula of (a) and write the  equations for all the reactions. 

Ans: C4H9Br is the chemical formula for two main primary alkyl halides. These are  given below: 

n-butyl bromide: CH3CH2CH2CH2Br

and Isobutyl bromide: 

(image will be uploaded soon)

As compound (a) when reacted with Na metal generated a compound (d) with a  molecular formula C H8 18which was different from the molecule obtained when n butyl bromide was reacted with Na metal, hence (a) must be isobutyl bromide and  compound (d) must be n-butyl bromide.

The reaction will be: 

$2CH_3CH_2CH_2CH_2Br + 2Na \overset{Wurtz reaction}\rightarrow CH_3(CH_2)_6CH_3$

(image will be uploaded soon)

Isobutyl bromide is compound (a). Because of this, 2-methyl-1-propane must be the  chemical (b) that it yields after being treated with alcohol KOH. The reaction is given  below: 

(image will be uploaded soon)

On treatment with HBr, compound (b) transforms into compound (c) in line with the  Markownikoff rule To summarise: Compound (c), also known as tert- butyl bromide,  is an isomer of compound (a), also known as isobutyl bromide. 

Therefore, (a) is isobutyl bromide, (b) is 2-Methyl-1-propane, (c) is tert-butyl bromide,  and (d) is 2, 5-Dimethylhexane. 


22. What happens when. 

(i)n-butyl chloride is treated with alcoholic KOH. 

Ans: When n-butyl chloride is treated with alcoholic KOH, then there will be  dehydrohalogenation and the product will be But-1-ene. The reaction is given below: 

(image will be uploaded soon)

(ii) Bromobenzene is treated with Mg in the presence of dry ether.

Ans: When bromobenzene is treated with Mg in the presence of dry ether there will be  the formation of Phenylmagnesium bromide. The reaction is given below: 

(image will be uploaded soon)

(iii)Chlorobenzene is subjected to hydrolysis. 

Ans: When chlorobenzene is hydrolyzed then there will be no reaction. 

(iv)Ethyl chloride is treated with aqueous KOH 

Ans: When ethyl chloride is treated with aqueous KOH then the product will be Ethyl  alcohol. The reaction is given below: 

$CH_3CH_2Cl + KOH (aq) \overset{Hydrolysis}\rightarrow CH_3CH_3OH + KCl$

(v) Methyl bromide is treated with sodium in the presence of dry ether. 

Ans: When methyl bromide is treated with sodium in the presence of dry ether then  Wurtz reaction will take place and the product of the reaction will be Ethane. The  reaction is given below: 

(image will be uploaded soon)

(vi)Methyl chloride is treated with KCN. 

Ans: When methyl chloride is treated with KCN then there will be a Nucleophilic substitution reaction and the product will be Methyl cyanide. The reaction is given  below: 

$CH_3-Cl + KCN \overset{ethanol}\rightarrow CH_3-C \equiv N + KCl$ 


NCERT Solutions for Class 12 Chemistry Chapter 10 PDF Download

Haloalkanes and Haloarenes class 12 NCERT solutions in PDF format, consists of an array of questions that are incorporated in the in-text Exercise and NCERT exercise. By following the various short answer and long answer type questions, in this PDF, students will get an in-depth understanding of every topic and subtopic of Haloalkanes and Haloarenes. Students can download the NCERT Solutions for Class 12 Chemistry Chapter 10 PDF for free from Vedantu.


Haloalkanes and Haloarenes Class 12 NCERT Solutions

Haloalkanes and Haloarenes are chemical compounds derived from alkanes and arenes containing one or more halogens. The NCERT solutions of this chapter broadly discuss the definitions, classifications, examples, and applications and other subtopics under Haloalkanes and Haloarenes. Also, students get to learn about the properties and preparations of organic halogen compounds from these NCERT solutions. The solution PDF consists of 32 questions, by solving which students will be able to grasp the concepts better. Also, they will learn to write the answers precisely as per the guidelines of the CBSE.


NCERT In-Text Exercise Solutions: Question-Wise Explanations

Question 1:

The very first question helps students to write structures of various compounds.

Question 2:

The solution to the second question enlightens students why instead of H2SO4, H3PO3 is used during the reaction of alcohols with KI.

Question 3:

While addressing this question, students will learn about four isomers that are possible answer choices. Therefore, they will be able to write four different dihalogen derivatives of propane.

Question 4:

The solution to this question guides students to identify the compound among the isomeric alkanes of molecular formula C5H12, which yields on photochemical chlorination.

Question 5 and 6:

Questions 5 and 6 deal with drawing the structures of major mono-halo products in given reactions and arranging a set of compounds in order of increasing boiling points respectively. Also, students will get to know the reasons followed in Question 6.

Question 7:

Students here get the explanation of which particular alkyl halide reacts more by an SN2 mechanism.

Question 8, 9, 10:

Questions 8 and 9 ask students to describe which compounds undergo faster SN1 reactions among the stated halogen compounds and to identify some aspects of a diagram, respectively.


Question 10 demands the identification of hydrocarbons that do not react with carbon in dark but gives a single mono-chloro compound C5H9Cl in broad daylight.

(image will be uploaded soon)


NCERT Exercise Solutions

Chemistry Class 12 Chapter 10

Question 1, 2, 3:

After studying question 1, students will be able to write names of halides according to the IUPAC system and classify them. Questions 2 and 3 help students to write the IUPAC names of various compounds and to draw the structures of organic halogen compounds, respectively.

Question 4, 5, 6:

Question 4 helps students to identify the highest dipole moment from among three provided options. Question 5 is the same as question 10 stated above. Question 6 demands students to write isomers of compounds which have the formula C4H9Br.

Question 7, 8:

The solution to question 7 helps students with writing equations for the preparation of 1-iodobutane from three given compounds. The solution to question 8 informs students about ambident nucleophiles with proper examples.


Apart from these, there are 14 other solutions to questions that deal with the following topics to help students to get a deeper understanding of the concepts.

  • Uses of freon 12, DDT.

  • Explanation of reactions under various conditions.

  • Structure of major organic products and others.


Class 12 Chemistry Chapter 10 NCERT Solutions: Marks Weightage

Chapter Name

Marks Weightage

Haloalkanes and Haloarenes 

4

Though the chapter carries fewer marks as compared to other chapters, students need to study every point in order to ace in the examination


A Brief Overview of NCERT Solutions For Class 12 Chemistry Chapter 10- Haloalkanes and Haloarenes 

Haloalkanes and Haloarenes are chemical compounds derived from alkanes and arenes containing one or more halogens. The NCERT Solutions for Chemistry Class 12 Chapter 10 pdf includes definitions, classifications, examples, applications, and other subtopics under Haloalkanes and Haloarenes. Also, students learn about the properties and preparations of organic halogen compounds from these NCERT solutions. The solution PDF consists of 32 questions, by solving which students will be able to grasp the concepts better. Also, they will learn to write the answers precisely per the CBSE guidelines.

 

Important Topics Covered In Class 12 Chemistry Chapter 10- Haloalkanes and Haloarenes 

  • Organic Chemistry Reactions (There are mainly four types of organic chemistry reactions, i.e., Addition, Substitution, and Elimination Reactions)

  • Nucleophilic Substitution Reactions

  • Substitution and Elimination: Saytzeff Rule and Hofmann Rules

  • Stereochemistry and its types

  • Alkyl Halides

  • Grignard Reagent

  • Special Alkyl Halides reactions

  • Aryl Halide

 

Class 12 Chemistry Chapter 10 Haloalkanes and Haloarenes: Some Important Points

  • The major difference between Haloalkanes and Haloarenes that we should remember is the presence of aromatic rings in Haloarenes, which are not found in Haloalkanes. Another important difference is that free-radical halogenation occurs in Haloalkanes but not in Haloarenes, Haloarenes possess a sweet odour, but Haloalkanes are odourless.

  • An important property of the C-X bond is that in haloalkanes, it is polarized. Halogen elements are more electronegative than carbon. Because of this high electronegativity, they attract the electron cloud more towards itself, which results in a slight negative charge; on the other hand, carbon obtains a slight positive charge.

  • Some important compounds of halogens are Dichloromethane, Trichloromethane, Tetrachloromethane, Iodoform, Freons, and DDT. 

 

Benefits of Referring to NCERT Solutions For Class 12 Chemistry Chapter 10 By Vedantu

The benefits of the NCERT solutions of Haloarenes and Haloalkanes are as follows.

  • These 100% accurate NCERT Solutions of Class 12 Chemistry Chapter 10 will guide the students to understand and write precise answers in the examination.

  • These NCERT solutions are designed under the guidance of skilled teachers. Hence every question is followed by logical explanations.

  • Also, these NCERT Solutions are prepared by following strict regulations of CBSE Board guidelines so that students can learn the proper answer patterns for their Chemistry board examination.

 

Therefore, Chemistry Class 12 students looking for reliable study resources for their preparation can download and refer to the Haloalkanes and Haloarenes Class 12 NCERT solutions on Vedantu.

 

Class 12 Chemistry Chapter 10 Haloalkanes and Haloarenes: Extra Questions For Practice

  1. How does the preparation of alkyl chloride is carried out?

  2. Explain Finkestian's reaction.

  3. What are nucleophiles?

  4. What is known as a racemic reaction?

  5. What are the uses of tetrachloromethane?

  6. Explain the Fitting reaction.

  7. What are known as ambident nucleophiles?

  8. Mention one use of DDT and iodoform.

  9. What happens when Ethyl chloride is treated with AgNO2?

  10. How will you convert Chlorobenzene to 2-chlorotoluene and Ethanol to propane nitrile?


Students are advised to download NCERT Solutions for Class 12 Chemistry Chapter 10  provided by Vedantu, as these questions will help them to clear the chapter concepts in a better way.  We suggest you practice these solutions after studying the topics covered in this chapter to appear for their Class 12th board exam with the confidence of scoring great marks. 


NCERT Solutions for Class 12 Chemistry Other Chapter Solutions 


Conclusion 

NCERT Solutions for Class 12 Chemistry Chapter 10 - Haloalkanes and Haloarenes are invaluable resources for students. These solutions provide comprehensive explanations and step-by-step answers to the various problems and questions presented in the chapter. They help students understand the complex concepts of haloalkanes and haloarenes, including nomenclature, preparation, reactions, and their significance in organic chemistry. NCERT Solutions not only facilitate better comprehension but also aid in exam preparation, ensuring that students can tackle questions effectively. Furthermore, they align with the curriculum, making them an essential tool for academic success. Overall, NCERT Solutions for Class 12 Chemistry Chapter 10 serve as an indispensable aid for students aiming to excel in their chemistry studies, offering clarity and guidance in this critical area of organic chemistry.

FAQs on NCERT Solutions for Class 12 Chemistry Chapter 10 - Haloalkanes And Haloarenes

1. Why Should I Refer to NCERT Solutions for Class 12 Chemistry Haloalkanes and Haloarenes PDF?

Haloalkanes and Haloarenes, the 10th chapter of Class 12 Chemistry deals with definitions, classifications, examples, and properties of halogen compounds. The solution provides an extensive study of physical and chemical properties, the various methods of preparation, and the usage of organo-halogen compounds.


By going through these NCERT solutions in PDF format, students will be able to name Haloalkanes and Haloarenes according to the IUPAC system of nomenclature from their provided structures. Also, students will get to learn different structures of major organic products in various reactions, mechanisms of a given reaction, usage of DDT, carbon tetrachloride, and so on. In short, the detailed discussion of the NCERT solutions helps students to understand the concept better.

2. How Does Haloalkanes and Haloarenes Class 12 NCERT Solutions Help Students?

NCERT Solutions Class 12 Chemistry Haloalkanes and Haloarenes revolves around the important methods of preparation, uses, and physical and chemical properties of organo-halogen compounds. Besides, each of the NCERT solutions is prepared by following the latest CBSE Board guidelines. The solutions help students to better understand the concept and score well in the 12th boards and other competitive examinations.

3. What are the Subtopics of the Chapter Haloalkanes and Haloarenes?

The chapter of Haloalkanes and Haloarenes consists of several sub-topics. They are – (1) Classification, (2) Nomenclature, (3) Nature of C-X Bond, (4) Methods of Preparation, (5) Physical properties, (6) Chemical Reactions, (7) Polyhalogen Compounds.


Students who intend to not only ace in the CBSE 12th board examinations but also in competitive exams like JEE can refer to these extensive study materials to get a better understanding of the topics covered in this chapter. Likewise, students who are finding it difficult to understand the underlying concept and sub-topics of Haloalkanes and Haloarenes may refer to various other related study materials on Vedantu, for a good exam preparation.

4. How do the NCERT Solutions for Chapter 10 of Class 12 Chemistry PDF help students?

Chapter 10 of Class 12 Chemistry deals with the preparation methods, applications, chemical and physical properties of Haloalkanes and Haloarenes. The NCERT Solutions are framed by the faculty having vast experience at Vedantu as per the latest CBSE guidelines and exam patterns. By referring to these solutions, students can easily understand the concepts better and score well in the board exams. They can also download the PDF format of solutions and can be used to check if their answers are right or wrong while answering the questions from the NCERT textbook. The solutions are available free of cost on the Vedantu website and the Vedantu app.

5. Explain why alkyl halides, though polar, are immiscible (not soluble) with water, according to Chapter 10 of Class 12 Chemistry?

Alkyl halides are polar molecules. That is the reason why their molecules are held together by dipole-dipole forces. Whereas the molecules of H20 are held together by the hydrogen bonds. So, when alkyl halides are added into water, the new forces of attraction between water and haloalkane molecules becomes weaker than the forces of attraction existing between alkyl halide-alkyl halide molecules and water-water molecules. Hence, alkyl halides, even though polar, are not soluble in water.

6. How to answer difficult questions of Chapter 10 of Class 12 Chemistry?

To answer the difficult questions of Chapter 10 of Class 12 Chemistry students must be well prepared with all the basic concepts. It is because having a strong knowledge of the fundamental concepts will help the students to answer any difficult questions. Students should give more importance to the topics that have more weightage and those important from the exam point of view. They should clear all their doubts regarding any chapter and have a clear knowledge of that full chapter.

7. Can I score high marks using the NCERT Solutions for Chapter 10 of Class 12 Chemistry?

Students can score high marks using the NCERT Solutions for Chapter 10 of Class 12 Chemistry as it guides them to prepare for the exams without fear. All the solutions are explained in a stepwise format helping the students to understand the concepts effortlessly. Wherever necessary, our faculty have provided diagrams in each important concept from the exam perspective, promoting visual learning. The solutions are written in crisp and clear as per the requirements of the exams.

8. Why should I download the Vedantu’s NCERT Solutions for Chapter 10 of Class 12 Chemistry PDF?

Students can benefit by downloading these NCERT Solutions for Chapter 10 of Class 12 Chemistry as they are created in an easy-to-understand language. This will help all the students to score good marks in their exams. NCERT Solutions will be helpful for the students not just for their CBSE exams but also for various competitive exams, JEE and NEET exams. Vedantu provides accurate and detailed solutions helping the students to clarify their doubts. It also increases confidence among students to appear for the exam.