Read the passage given below and answer the following questions:
Haloarenes are less reactive than haloalkanes. The low reactivity of haloarenes can be attributed to
(i) resonance effect
(ii) Sp² hybridisation of C - X bond
(iii) polarity of C - X bond
(iv) instability of phenyl cation (formed by self-ionisation ofhaloarene)
(v) repulsion between the electron rich attacking nucleophiles and electron rich arenes.
Reactivity of haloarenes can be increased or decreased by the presence of certain groups at certain positions for example, nitro (-NO₂) group at olp positions increases the reactivity of haloarenes towards nucleophilc substitution reactions.
The following questions are multiple choice questions. Choose the most appropriate answer:
(i) Aryl halides are less reactive towards nucleophilic substitution reaction as compared to alkyl halides due to

(ii) Which of the following aryl halides is the most reactive towards nucleophilic substitution?

(iii) Which one of the following will react fastest with aqueous NaOH?

The reactivity of the compounds (i) MeBr, (ii) PhCH₂Br, (iii) MeCI, (iv) p- MeOC₆H₄Br decreases as

Read the passage given below and answer the following questions:
In haloalkanes, when a nucleophile stronger than the halide ion approaches the positively charged carbon atom of an alkyl halide, the halogen atom along with its bonding electron pair gets displaced and a new bond with the carbon and the nucleophile is formed. These reactions are called nucleophilic substitution reactions.

In these reactions the atom or group of atoms which loses its bond from carbon and takes on an additional pair of electrons is called leaving group. Halide ions are good leaving groups. Some important nucleophilic substitution reactions of haloalkanes with common nucleophiles are given in the table below.

In these questions (i-iv), a statement of assertion followed by a statement of reason is given. Choose the correct answer out of the following choices.
(a) Assertion and reason both are correct statements and reason is correct explanation for assertion.
(b) Assertion and reason both are correct statements but reason is not correct explanation for assertion.
(c) Assertion is correct statement but reason' is wrong statement.
(d) Assertion is wrong statement but reason is correct statement.
(i) Assertion: Alkyl halides are hydrolysed to alcohols by moist silver oxide.
Reason: RCI is hydrolysed to ROH easily but reactions slow down on addition of KI.
(ii) Assertion : Alkyl halides form alkenes when heated above 300°C.
Reason: CH₃CH₂I reacts slowly with strong base as compared to CD₃CH₂I.
(iii) Assertion : RBr reacts with AgNO₂ to give nitro alkane.
Reason: Silver nitrite (AgNO₂) is an ionic compound, therefore the negative charge on nitrogen is the attacking site.
(iv) Assertion: The nucleophilic substitution of vinyl chloride is difficult than ethyl chloride.
Reason: Vinyl group is electron donating group.

Read the passage given below and answer the following questions:
When a chemical reaction involves bond cleavage or bond formation at an asymmetric carbon atom, three different products may be formed. For example, during the substitution of a group X by Y in the following reaction, the three possible products may be shown below:

(i) If B is the only product, the process is called retention of configuration because B has the same configuration as the starting reactant (A).
(ii) If C is the only product, the process is called inversion of configuration because C has the configuration opposite to the starting reactant (A).
(iii) If an equimolar mixture of B and C (i.e., a 50 : 50 mixture) is formed, then the process is called racemisation and the product is optically inactive because one isomer will rotate the light in the direction opposite to another.
In these questions ( i-iv), a statement of assertion followed by a statement of reason is given. Choose the correct answer out of the following choices.
(a) Assertion and reason both are correct statements and reason is correct explanation for assertion.
(b) Assertion and reason both are correctstatements but reason is not correct explanation for assertion.
(c) Assertion is correct statement but reason is wrong statement.
(d) Assertion is wrong statement but reason is correct statement.
(i) Assertion: A reaction is said to be stereospecific if a particular stereoisomer of the reactant produces a specific stereoisomer of the product.
Reason: Bromination of cis-2-butene gives meso-2, 3-dibromobutane which is stereospecific
(ii) Assertion: Addition of Br₂ to cis-but-2-ene is stereoselective.
Reason: S_N2 reactions are stereospecific as well as stereoselective.
(iii) Assertion: Optically active 2-iodobutane on treatment with NaI in acetone undergoes recemization.
Reason: Repeated Walden inversions on the reactant and its product eventually gives a racemic mixture.
(iv) Assertion: S_N2 reaction of an optically active alkyl halide with an aqueous solution of KOH always gives an alcohol with opposite sign of rotation.
Reason: S_N2 reactions always proceed with inversion of configuration.

Read the passage given below and answer the following questions:
The order of reactivity towards S_N1 reaction depends upon the stability of carbocation in the first step. Greater the stability of the carbocation, greater will be its ease of formation from alkyl halide and hence faster will be the rate of the reaction. As we know, 3° carbocation is most stable, therefore, the tert-alkyl that halides will undergo S_N1 reaction very fast. For example, it has been observed that the reaction (CH₃)₃CBr with OH^- ion to give 2-methyl-2-propanol is about 1 million times as fast as the corresponding reaction of the methyl bromide to give methanol.
The primary alkyl halides always react predominantly by S_N2 mechanism. On the other hand, the tertiary alkyl halides react predominantly by S_N1 mechanism. Secondary alkyl halides may react by either mechanism or by both the mechanisms without much preference depending upon the nature of the nucleophile and solvent.
In these questions ( i-iv), a statement of assertion followed by a statement of reason is given. Choose the correct answer out of the following choices.
(a) Assertion and reason both are correct statements and reason is correct explanation for assertion.
(b) Assertion and reason both are correct statements but reason is not correct explanation for assertion.
(c) Assertion is correct statement but reason is wrong statement.
(d) Assertion is wrong statement but reason is correct statement.
(i) Assertion: Low concentration of nucleophile favours S_N1mechanism.
Reason: 2° alkyl halides are less reactive than 1° towards S_N1 reactions.
(ii) Assertion: Polar solvent slows down S_N2reactions.
Reason: CH₃-Br is less reactive than CH₃Cl.
(iii) Assertion: Benzyl bromide when kept in acetone- water it produces benzyl alcohol.
Reason: The reaction follows S_N2 mechanism.
(iv) Assertion: Rate of hydrolysis of methyl chloride to methanol is higher in DMF than in water.
Reason: Hydrolysis of methyl chloride follows second order kinetics.

Read the passage given below and answer the following questions:
The aryl halides are relatively less reactive towards nucleophilic substitution reactions as compared to alkyl halides. This low reactivity can be attributed to the following factors:
1. The C - X bond in halobenzene has a partial double bond character due to involvement of halogen electrons in resonance with benzene ring.
2. The C - X bond in aryl halides is less polar as compared to that in alkyl halides as sp² hyridised carbon is more electronegative than sp³ hybridised carbon.
In these questions ( i-iv), a statement of assertion followed by a statement of reason is given. Choose the correct answer out of the following choices.
(a) Assertion and reason both are correct statements and reason is correct explanation for assertion.
(b) Assertion and reason both are correct statements but reason is not correct explanation for assertion.
(c) Assertion is correct statement but reason is wrong statement.
(d) Assertion is wrong statement but reason is correct statement.
(i) Assertion: Primary benzylic halides are more reactive than primary alkyl halides towards S_N1 reactions.
Reason: Reactivity depends upon the nature of the nucleophile and the solvent.
(ii) Assertion : is more reactive than towards nucleophilic substitution reactions.
Reason: Tertiary alkyl halides react predominantly by S_N1 mechanism.
(iii) Assertion: Chlorobenzene is more reactive than p-chloroanisole to nucleophilic substitution reactions.
Reason: Greater the stability of'carbanion, greater is its ease of formation and hence, more reactive is the aryl halide.
(iv) Assertion: Chlorobenzene is less reactive than benzene towards the electrophilic substitution reaction.
Reason: Resonance destabilises the carbo cation.