Introduction to Chemical Reactions

Q. Which of the following is most reactive towards electrophilic substitution reaction ?

1. 
2. 
3. 
4. 

Q.

What are important electron withdrawing groups and electron donating groups should be remembered for NEET examination point of view..?

Q. 1) Which alkyl halide from the following pairs would you expect to react more rapidly by and $S_{N}2$ mechanism?
Explain you answer.


2) Which alkyl halide from the following pairs would you expect to react more rapidly by and $S_{N}2$ mechanism?
Explain you answer.


3) - Which alkyl halide from the following pairs would you expect to react more rapidly by and $S_{N}2$ mechanism?
Explain you answer.

Q.

What is meant by activating or deactivating a benzene ring?

Q. Which one of the following compounds will give orange percipitate when treated with 2, 4-dinitrophenyl hydrazine?

1. 
2. 
3. 
4. 

Q.

What is the major product of chlorination of ethylbenzene?

Q. A compound with molecular mass 180 is acylated with $C{H}_{3}COCl$ to get a compound with molecular mass 390. The number of amino groups present per molecule of the former compound is

1. 2
2. 5
3. 4
4. 6

Q. The following is not an appropriate reaction for the preparation of $t-butylethylether$.


$A$: What would be the major product of this reaction?

$B$: Write a suitable reaction for the preparation of $t-butylethylether$.

Q.

Write the reaction for the conversion of ethene to chloroethane.

Q. Which of the following reactions will not result in the formation of anisole?

1. 
2. 
3. 
4. 

Q. Why do alkenes prefer to undergo electrophilic addition reactions while arenes prefer electrophilic substitution reactions? Explain.

Q. Which of the following is not a nucleophile?

1. $O{H}^{-}$
2. $C{N}^{-}$
3. $B{F}_3$
4. $N{H}_3$

Q. Aniline reacts with mixed acid(conc.$HN{O}_3$ and conc.$H_{2}S{O}_4$ at 288K to give P (51%), Q (47%) and R(2%) . The major product(s) of the following reaction sequence is (are)

1. 
2. 
3. 
4. 

Q. Ethylbenzene is generally prepared by acetylation of benzene followed by reduction and not by direct alkylation. Think of a possible reason.

Q. Which of the following statements is not true about glucose?

1. It is an aldohexose.
2. It is present in furanose form.
3. On heating with $HI$, it forms $n-$hexane.
4. It does not give $2,4-DNP$ test.

Q.

Chlorine reacts with water in presence of sunlight to liberate________

Q. Which is the strongest nucleophilic site in the following species?

Q.

Write the reaction of ethene with $\mathrm{HCl}$.

Q. Show how are the following alcohols prepared by the reaction of a suitable Grignard reagent on methanal ?

A
B

Q. The no. Of antibonding electron pairs in O2 one negative

Q. A:1-chloro-2, 4-nitrobenzene is more reactive towards nucleophillic substitution reaction than chlorobenzene R:NO2 group is electron withdrawing so decteases the double bond character of C-Cl bond.

Q.

Write the equations for the reaction of Ethylene with bromine

Q.

Write the structures of products of the following reactions;

(i)

(ii)

(iii)

(iv)

Q. $A+CC{l}_4+KOH\to \text{Salicylic acid}$
${}^{\prime }{A}^{\prime }$ in above reaction is

1. 
2. 
3. 
4. 

Q.

Which of the following compounds reacts with${\mathrm{NaNO}}_2$and $\mathrm{HCl}$ at $-4°\mathrm{C}$ to yield alcohol (or) phenol?

1. ${\mathrm{C}}_2{\mathrm{H}}_5{\mathrm{NH}}_2$

2. ${\mathrm{C}}_6{\mathrm{H}}_5{\mathrm{NH}}_2$

3. ${\mathrm{CH}}_3{\mathrm{NHCH}}_3$

4. ${\mathrm{C}}_6{\mathrm{H}}_5{\mathrm{NHCH}}_3$

Q.

Amino group is ortho, para directing for aromatic electrophilic substitution. On nitration of aniline with concentrated acids, a good amount of meta nitro aniline is obtained. This is due to

1. - NH₂ becomes - NH ^-NO₂⁺, which is meta directing
2. - NH₂ becomes - NH ⁺SO₄^-2, which is meta directing
3. - NH₂ becomes - NH₃ ⁺, which is meta directing
4. In nitration mixture, ortho and para activity of NH₃ group is completely lost

Q. 6. Synthesis m-dibromobenzene from benzene ?? What is the method to do conversions?

Q. 15. Conversion of chlorobenzene to 2-chlorotoluene

Q. Identify the major and minor products in the following reactions9-->(i)CH, -CH-CH-CH(CH, ), + HBr09What is the major product formed in the following reaction?CH-O-CH-CH-CH3 +HBr-

Q.

Ostwald's process is used to manufacture:

1. Nitrous acid

2. Ammonia

3. Nitric acid

4. Sulphuric acid