Read the passage given below and answer the following questions:
Amines are basic in nature. The basic strength of amines can be expressed by their dissociation constant, K_b or pK_{b.
\(\mathrm{RNH}_{2}+\mathrm{H}_{2} \mathrm{O} \rightleftharpoons \mathrm{RNH}_{3}^{+}+\mathrm{OH}^{-}\)
\(K_{b}=\frac{\left[R \mathrm{NH}_{3}^{+}\right]\left[\mathrm{OH}^{-}\right]}{\left[R \mathrm{NH}_{2}\right]} \text { and } \mathrm{p} K_{b}=-\log K_{b}\)}
Greater the K_b value or smaller the pK_b value, more is the basic strength of amine. Aryl amines such as aniline are less basic than allphatic amines due to the involvement of lone pair of electrons on N-atom with the resonance in benzene. In derivatives of aniline, the electron releasing groups increase the basic strength while electron withdrawing groups decrease the basic strength. The base weakening effect of electron withdrawing group and base strengthening effect of electron releasing group is more marked at p-position than at m-position. o-Substituted aniline is less basic than aniline due to ortho effect and is probable due to combination of electronic and steric effect.
The following questions are multiple choice questions.Choose the most appropriate answer :
(i) Which of the following has lowest pK_b value?

(ii) The strongest base among the following is

(iii) Maximum pK_b value of

(c) (CH3CH2)2NH	(d) (CH3)2NH

(iv) Which of the following statements is not correct?

Read the passage given below and answer the following questions:
RCONH₂ is converted into RNH₂ by means of Hoffmann bromamide degradation. During the reaction amide is treated with Br₂ and alkali to get amine. This reaction is used to descend the series in which carbon atom is removed as carbonate ion (CO₃^2-). Hoffmann bromide degradation reaction can be written as :

The following questions are multiple choice questions. Choose the most appropriate answer:
(i) Hoffmann bromamide degradation is used for the preparation of

(ii) Which is the rate determining step in Hoffmann bromamide degradation?

(iii) Which of the following are used for the conversion of (i) to (ii)?

(iv) What are the constituent amines formed when the mixture of (i) and (ii) undergoes Hoffmann bromamide degradation?

Read the passage given below and answer the following questions:
Amines are produced when an alcoholic solution of ammonia and an alkyl or a benzyl halide is heated in a sealed tube at 373 K. This reaction is called ammonolysis and usually gives a mixture of primary, secondary and tertiary amines along with some quarternary ammonium salts. This reaction is an example of nucleophilic substitution reaction in which ammonia acts as a nucleophile due to the presence of a lone pair of electrons on the nitrogen atom. However this method cannot be used for the preparation of aryl amines. One of the most convenient methods for the preparation of aryl amines is reduction of nitro compounds. Aryl amines can also be prepared by reduction of nitrites or Gabriel phthalimide synthesis.
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: Ammonolysis of alkyl halides only produces 2^o amines.
Reason: Ammonolysis of alkyl halides involves the reaction between alkyl halides and alcoholic ammonia.
(ii) Assertion: Ammonolysis method cannot be used for the preparation of aryl amines.
Reason: Aryl halides are much less reactive than alkyl halides towards nucleophilic substitution reaction.
(iii) Assertion: Ammonolysis can be used to prepare pure primary amines.
Reason: Ammonolysis of haloalkanes lead to multiple ammonium salts.
(iv) Assertion: Aromatic 1^p amines can not be prepared by Gabriel phthalimide synthesis.
Reason: Aryl halides do not undergo nucleophilic substitution with anion formed by phthalimide.

Read the passage given below and answer the following questions:
Aniline activates the benzene ring by increasing electron density at ortho- and para-positions. Hence, it is o-, p-directing. -NH₂ group strongly activates the ring therefore it is difficult to stop the reaction at monosubstitution stage. Among electrophilic substitution reaction, direct nitration of aniline is not done to get o- and p-nitroaniline because lone pair of electrons present at nitrogen atom will accept proton from nitrating mixture to give anilinium ion which is meta-directing. Aniline with NaNO₂ and HCl forms benzene diazonium chloride at very low temperature. Aromatic amines react with nitrous acid to form a yellow oily liquid known as N-nitrosoamines.
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: Nitrating mixture used for carrying out nitration of benzene consists of cone. conc. HNO₃ +conc. H₂SO₄ .
Reason: In presence of H₂SO₄ , HNO₃ acts as a base and produces NO₂⁺ ions.
(ii) Assertion: Anilinium chloride is more acidic than ammonium chloride.
Reason: Anilinium ion is not resonance-stabilised.
(iii) Assertion: Nitrobenzene can be prepared from benzene by using mixture of conc. HNO₃ and conc. H₂SO₄ .
Reason: In the mixture,H₂SO₄ act as a acid.
(iv) Assertion: In strongly acidic solution, aniline becomes less reactive towards electrophilic reagents.
Reason: The amino group being completely protonated in strongly acidic solution, the lone pair of electrons on the nitrogen is no longer available for resonance.