Haloalkanes and Haloarenes

CBSE Class 12 Chemistry · every board question from this chapter, 2023–2026 · 42 of them repeated across years

• Which of the following will be the least reactive towards nucleophilic substitution reaction?2026
• Which of the following is not correct for S N 1 reaction?2026
• Oxidation of chloroform by air in the presence of sunlight produces a poisonous gas known as:2026
• Which of the following, compounds is most reactive towards nucleophilic substitution reaction with aqueous NaOH?2026
• The position of - Br in the compound can be classified as:2026
• Consider the following reaction and identify A and B: CH 3 Cl+NaI dry acetone A+B2026asked 3×
• Which of the following is 'not' true about enantiomers?2026asked 3×
• Consider the following compounds: Chlorobenzene (I), 2,4,6-trinitrochlorobenzene (II), 2,4-dinitrochlorobenzene (III),…2026
• For the compound having molecular formula C 4 H 9 Br, write: the isomer which is most reactive towards S N 1 displacement. the…2026asked 3×
• Why are haloarenes less reactive towards nucleophilic substitution reaction? Give two reasons.2026asked 3×
• Complete the equation: How will you convert chlorobenzene to p-chloroaniline?2026
• Write the major product in the following reaction: What happens when 2-Bromobutane is made to react with alcoholic potassium…2026
• Draw the structure of the given compound: 4-Bromo-3-methylpent-2-ene What happens when chloroethane is treated with aqueous…2026asked 2×
• Draw the structures of major products in each of the following reactions: 2 (CH 3) 3 CBr+KOH [ Heat ] Ethanol2026
• Draw the structures of major product(s) in each of the following reactions: CH 3 CH=C(CH 3) 2+HBr →2026
• Give reasons for the following: Alkyl halides, though polar, yet their solubility in water is very low. p-Dichlorobenzene has…2026
• Write the major product in the following reactions: 1+1+1 Define Racemic mixture. p-dichlorobenzene has a higher melting point as…2026
• Give reasons for the following: Although chlorine is an electron-withdrawing group, yet it is ortho-, para-directing in…2026
• Write the major product in the following reaction: 1+1+1 Define Chirality. Why racemisation occurs in S N 1 reaction?2026
• Write the IUPAC name of the given compound: CH 3 CH(CH 3) CH(Br) CH 3 1+1+1 Define Racemisation. The boiling points of the alkyl…2026
• Give reasons for the following: Haloalkanes react with KCN to form alkyl cyanides, while with AgCN, they form isocyanides. is…2026
• Compound 'X' with molecular formula C 4 H 9 Br reacts with aqueous KOH to give an alcohol. The rate of this reaction depends only…2026asked 3×
• Answer the following: Which isomer of C 4 H 9 Br is most reactive towards S N 1 reaction? Predict the alkene that would be formed…2026asked 3×
• (i) (I) Which of the following is more reactive towards S N 1 reaction: 2-Bromo-2-methylbutane or 1-Bromopentane (II) What type…2026asked 3×
• Which reagents are required for one step conversion of chlorobenzene to toluene?2025
• Which reagents are required for one step conversion of Chlorobenzene to Diphenyl?2025
• Which of the following compounds would be hydrolysed by aqueous KOH most easily?2025
• Arrange the following compounds in increasing order of their boiling points: (i) (ii) CH 3CH 2CH 2CH 2Br (iii) The correct order…2025asked 3×
• The treatment of ethyl bromide with alcoholic silver nitrite gives:2025asked 3×
• Which of the following haloalkanes react with aqueous KOH most rapidly by S N 1 reaction?2025
• Which of the following haloalkanes is most reactive towards S N 2 reaction?2025
• Out of 2-Bromobutane, 1-Bromobutane, 2-Bromopropane and 1-Bromopropane, the molecule which is chiral in nature is:2025asked 3×
• Alkyl halides undergoing nucleophilic bimolecular substitution reaction involve2025asked 3×
• The synthesis of alkyl fluoride is best carried out by:2025
• Polyhalogen compounds have wide application in industries and agriculture. DDT is also a very important polyhalogen compound. It…2025asked 3×
• While doing qualitative analysis in chemistry lab, Abhishek added yellow coloured potassium chromate solution into a test tube.…2025asked 3×
• Assertion: The boiling points of alkyl halides decrease in the order: RI RBr RCl RF. Reason (R): The boiling points of alkyl…2025asked 3×
• Assertion: n-Butyl chloride has higher boiling point than n-Butyl bromide. Reason (R): C - Cl bond is more polar than C - Br bond.2025asked 3×
• Assertion: The boiling points of alkyl halides decrease in the order RI RBr RCl RF. Reason (R): The van der Waals forces of…2025asked 3×
• Why are haloarenes less reactive towards nucleophilic substitution reaction? How does the presence of nitro (-NO 2) group at…2025asked 3×
• Draw the structures of major monohalo products in each of the following reactions:2025
• In the following pair of halogen compounds, which compound undergoes S N 1 reaction faster and why? Arrange the following…2025asked 2×
• Give reasons for the following observations: 1 + 1 p-Chloronitrobenzene reacts with (aq) NaOH at 443 K to give p-nitrophenol…2025
• Draw the structures of the major monohalo products in each of the following reactions:2025
• Account for the following: (i) Allyl chloride is hydrolysed more readily than n-propyl chloride. (ii) Isocyanides are formed when…2025asked 3×
• Write structure of the products of the following reactions: conc. HNO 3 →2025
• Write any two differences between S N 1 and S N 2 reactions. Which of the following compounds would undergo S N 1 reaction faster…2025asked 3×
• A compound with molecular formula C 4 H 9 I which is a primary alkyl halide, reacts with alcoholic KOH to give compound. Compound…2025asked 3×
• Account for the following: Haloarenes are less reactive towards nucleophilic substitution reactions. p -dichlorobenzene has…2025
• Among the following, which will have inversion of configuration on reaction with aqueous alkali and why? (i) 1-chloropropane OR…2025
• Account for the following: The C - Cl bond length in chlorobenzene is shorter than that in methyl chloride. Grignard reagents…2025
• Define the following: 2+1=3 (i) Enantiomers (ii) Racemic mixture Why is chlorobenzene resistant to nucleophilic substitution…2025asked 3×
• Draw the structure of the major monohalo product for each of the following reaction: (1+1+1=3) How do you convert: Chlorobenzene…2025asked 3×
• Auto-oxidation of chloroform in air and light produces a poisonous gas known as2024asked 3×
• Which of the following is a benzylic halide?2024
• Which alkyl halide from the given options will undergo S N 1 reaction faster?2024asked 3×
• The compound which undergoes S N 1 reaction most rapidly is:2024
• Which of the following is most reactive towards nucleophilic substitution reaction?2024
• Assertion: Inversion of configuration is observed in S N 2 reaction. Reason (R): The reaction proceeds with the formation of…2024asked 2×
• Assertion: Inversion of configuration is observed when 1-Bromobutane is hydrolysed. Reason (R): The reaction is S N 2 and…2024
• Which one of the following pairs of substances undergoes S N 1 reaction faster and why? CH 3-CH 2-CH 2-Cl OR CH 2=CH-CH 2-Cl…2024
• In the following pair of compounds, which compound undergoes S N 1 reaction faster and why? OR Write the major product in the…2024
• Which compound in the given pair would undergo S N 2 reaction at a faster rate and why? CH 3-CH 2-I and CH 3-CH 2-Br Arrange the…2024
• Which of the following compounds will react more rapidly by S N 1 reaction and why? or CH 3 CH 2 Br Arrange the following…2024
• Which of the following compounds will react more rapidly by S N 2 reaction \& why? or Arrange the following compounds in the…2024
• Which halogen compound in the following pair will react faster in S N 1 reaction and why? or Why is the dipole moment of…2024
• Draw the structures of major monohalo products in each of the following reactions: (i) (ii) OR Give reasons for the following:…2024
• Which halogen compound in the following pair will react faster in S N 2 reactions and why? CH 3-CH 2-I OR CH 3-CH 2-Br Why is…2024
• In the following pair of compounds, which compound undergoes S N 2 reaction faster and why? Write the major product in the…2024
• Which halogen compound in the following pair will react faster in S N 2 reaction and why? OR Why does the presence of nitro…2024
• Which of the following is an allylic halide? (i) CH 3-CH=CH-Br (ii) Out of chlorobenzene and 2,4,6-trinitrochlorobenzene, which…2024asked 3×
• Give reasons for the following: Chlorine is ortho/para directing in electrophilic aromatic substitution reactions, though…2024asked 3×
• What type of nucleophilic substitution (S N 1. or.S N 2) occurs in the hydrolysis of 2-Bromobutane to form (±)-Butan-2-ol? Give…2024asked 3×
• Account for the following: 1 × 3 Haloalkanes react with AgCN to form isocyanide as main product. Allyl chloride shows high…2024asked 2×
• Write the IUPAC name of the given compound: Why are haloalkanes more reactive towards nucleophilic substitution reactions than…2024
• Write the IUPAC name of the given compound: CH 2=CH-CH 2-CH 2-Cl Why is thionyl chloride preferred for preparing alkyl halides…2024
• Write the IUPAC name of the given compound: The presence of -NO 2 group at ortho or para position increases the reactivity of…2024
• Account for the following: 1 × 3 Haloalkanes react with NaCN to form both cyanides and isocyanides. Haloarenes do not undergo…2024
• Which of the following has the highest melting point?2023
• Auto oxidation of chloroform in air and sunlight produces a poisonous gas known as2023
• The conversion of an alkyl halide into an alkene by alcoholic KOH is classified as2023
• Which of the following belongs to the class of Vinyl halides?2023
• Which of the following belongs to the class of alkyl halides?2023
• Reaction of 1-phenyl-2-chloropropane with alcoholic KOH gives mainly:2023asked 3×
• Retention of configuration is observed in2023
• Racemisation occurs in 12023
• Inversion of configuration occurs in2023
• The species that attacks benzene in following is:2023
• The synthesis of alkyl fluoride is best obtained from:2023asked 2×
• Which of the following reactions are feasible?2023asked 3×
• Assertion: Chlorobenzene is resistant to electrophilic substitution reaction. Reason (R): C-Cl bond in chlorobenzene acquires…2023
• Assertion: Bromination of benzoic acid gives m-bromobenzoic acid. Reason (R): Carboxyl group increases the electron density at…2023
• Assertion: Nucleophilic substitution of iodoethane is easier than chloroethane. Reason (R): Bond energy of C - Cl bond is less…2023asked 3×
• Assertion: Chlorobenzene is resistant to nucleophilic substitution reaction at room temperature. Reason (R): C-C l bond gets…2023
• Assertion: Nucleophilic substitution of iodoethane is easier than chloroethane. Reason (R): Bond enthalpy of C-I bond is less…2023
• An alkyl halide of molecular formula C 6 H 13 Cl on treatment with alcoholic KOH gives two isomeric alkenes and of molecular…2023asked 3×
• Why haloarenes are not reactive towards nucleophilic substitution reaction? Give two reasons.2023
• Why is boiling point of o-dichlorobenzene higher than p-dichlorobenzene but melting point of para isomer is higher than ortho…2023
• Write equations for the following: Oxidation of chloroform by air and light Reaction of chlorobenzene with CH 3 Cl / anhyd. A l…2023
• Write the main product formed when: n-Butyl chloride is treated with alc. KOH. 2,4,6-Trinitrochlorobenzene is subjected to…2023
• CH 3 CH 2 CH 2 Cl+KOH ethanol 'A' HBr 'B' Identify'A'and'B'in the above reactions.2023asked 2×
• Answer any 3 of the following: 3 × 1 Which isomer of C 5 H 10 gives a single monochloro compound C 5 H 9 C l in bright sunlight?…2023asked 3×
• Complete the following reactions: 1 1/2+1 1/2=3 CH 3 CH 2 CH 2 Br [Δ] Alc. KOH HBr2023
• Account for the following: Benzyl chloride is highly reactive towards S N 1 reaction. (±)-Butan-2-ol is optically inactive,…2023asked 3×
• Write main product formed when: Methyl chloride is treated with NaI/Acetone. 2,4,6-trinitrochlorobenzene is subjected to…2023asked 2×
• The polarity of C - X bond of alkyl halides is responsible for their nucleophilic substitution, elimination and their reaction…2023asked 3×
• Nucleophilic Substitution Nucleophilic Substitution reaction of haloalkane can be conducted according to both S N 1 and S N 2…2023asked 2×
• Nucleophilic Substitution Nucleophilic Substitution reaction of haloalkane can be conducted according to both S N1 and S N2…2023

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