Explore topic-wise InterviewSolutions in Current Affairs.

This section includes 7 InterviewSolutions, each offering curated multiple-choice questions to sharpen your Current Affairs knowledge and support exam preparation. Choose a topic below to get started.

1.

Benzophenone does not react with NaHSO_(3). Explain.

Answer»

Solution :The reaction of `NaHSO_(3)` with BENZOPHENONE involves the nucleophilic ATTACK of `HSO_(3)^(-)` (BISULPHITE) ion. Benzophenone being is less being REACTIVE, does not react with weak NUCLEOPHILE `NaHSO_(3)`.
Discussion
2.

Benzoyl chloride does not react with :

Answer»

PRIMARY or secondary amine
ALIPHATIC COMPOUND
AROMATIC COMPOUNDS
Carboxylic acids

Answer :D
Discussion
3.

Benzophenone is obtained from Ph-MgX and what

Answer»

Benzaldehyde
Benzoic acid
Benzonitrile
2-phenyl ETHANE nitrile

Answer :C
Discussion
4.

Benzoquinone, is prepared by reaction of phenol with

Answer»

`Na_2Cr_2O_7, H_2SO_4`
`KMnO_4, H_2SO_4`
`Na_2CrO_4 , HCL`
`K_2MnO_4, H_2SO_4`

ANSWER :A
Discussion
5.

Benzophenone can be obtained by____

Answer»

Benzoyl chloride+Benzene`+AlCl_(3)`
Benzoyl chloride+Diphynylcadmium
Benzoyl chloride+Phenylmagnesium chloride
Benzene+Carbon monoxide`+ZnCl_(2)`

SOLUTION :(a). `underset("Benzoyl chloride")(C_(6)H_(5)COCl)+C_(6)H_(6) underset(("F.C. acylation")) overset("Anhyd. "AlCl_(3))tounderset("BENZOPHENONE")(C_(6)H_(5)COC_(6)H_(5))+HCl`
(b) `underset("Benzoyl chloride")(2C_(6)H_(5)COCl)+(C_(6)H_(5))_(2)Cd overset("Dry ether")to underset("Benzophenone")(2C_(6)H_(5)COC_(6)H_(5))+CdCl_(2)`
Discussion
6.

Benzophenone (C_(6)H_(5)COC_(6)H_(5)) will react with

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`NaHSO_(3)`
`CH_(3)OH`
`HCN`
`NH_(2)OH`

Solution :Due to +R-effect of the TWO phenyl groups, the POSITIVE CHARGE on the C-atom of the CO group is diminished to such an extent that weak nucleophiles such as HCN, `NaHSO_(3)` and `CH_(3)OH` do not react with benzophenone. Therefore, only `NH_(2)OH` reacts.
Discussion
7.

Benzophenone can be obtained by I. Benzoyl chloride +Benzene+AlCl_(3) II. Benzoyl chloride + Diphenyl cadmium ltbr. III. Benzoyl chloride+Phenyl magnesium chlorideltbr. IV. Benzene+ Carbon monoxide+ ZnCl_(2) Select an appropirate option

Answer»

(i) and (II)
(ii) and (III)
(i) and (iii)
(i), (ii) and (iii)

SOLUTION :
Discussion
8.

Benzophenone does not react with

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`RNH_(2)`
`SO_(3)`
`NaOH`
`Na_(2)CO_(3)`

SOLUTION :Except `Na_(2)CO_(3)` benzophenone react with rest of option.
Discussion
9.

Benzoin is formed when benzaldehyde is treated with_________.

Answer»

SOLUTION :ALCOHOLIC KCN.
Discussion
10.

Benzonitrile and phenyl magnesium bromide produces

Answer»




ANSWER :A
Discussion
11.

Benzophenone (C_(6)H_(5)COC_(6)H_(5)) does notreact with

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`NaHSO_(3)`
`CH_(3)OH`
HCN
`NH_(2)OH`

ANSWER :A::B::C
Discussion
12.

Benzoin is ________

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an `ALPHA`-HYDROXY ALDEHYDE
`BETA`-hydroxy aldehyde
`beta`- hydroxy KETONE
`alpha` - hydroxy ketone

Answer :D
Discussion
13.

Benzoin is

Answer»

 compound CONTAINING an aldehyde and a ketonic GROUP
`ALPHA,BETA`-unsaturated acid
a-hydroxy aldehyde
a-hydroxy ketone.

Solution :
Discussion
14.

Benzoic acid, when heated with soda lime gives ______

Answer»

`C_(6)H_(5)COONA`
`C_(6)C_(5)COOC_(6)H_(5)`
`C_(6)H_(6)`
`C_(6)H_(5)OH`

Answer :C
Discussion
15.

Benzoic acid when heated with sodalime gives:

Answer»

BENZENE
SODIUM benzoate
benzaldehyde
BENZYL alcohol

Answer :A
Discussion
16.

"Benzoic acid"underset("ii)"Delta)overset("i)"NH_(3))toAoverset(NaOBr)toBoverset(NaNO_(2)//HCl)toC'C' is

Answer»

anilinium CHLORIDE
O - NITRO aniline
benzene diazonium chloride
m - nitro benzoic acid

Solution :`C_(6)H_(5)COOHunderset((II)Delta)overset((i)NH_(3))(rarr)C_(6)H_(5)CONH_(2)overset(NaOBr)(rarr)C_(6)H_(5)-NH_(2)overset(NaNO_(2)//HCl)(rarr)C_(6)H_(5)-N=N-Cl`
Discussion
17.

Benzoic acid undergoes dimerisation in benzene solution, the vat't Hoff factor 'I' is related to the degree of association 'x' of the acid as

Answer»

i=(1-X)
i=(1+x)
i=(1-x/2)
i=(1+x/2)

SOLUTION :`2C_(6)H_(5)COOH rarr (C_(6)H_(5)COOH)_(2)`
Before asso. 1 MOL
After asso. `1 - x x/2`
total`=1 - x + x/2` = `1- x/2`
`i=(1-x//2)/1` "or" `i=1 - x/2`
Discussion
18.

Benzoic acid undergoes dimerisation in benzene solution. The van't Hoff factor (i) is related to the degree of association 'x' of the acid as

Answer»

`i=(1-x)`
`i=(1+x)`
`i=(1-x//2)`
`1=(1+x//2)`

Solution :`{:(,2C_(6)H_(5)COOH,hArr,(C_(6)H_(5)COOH_(2))),("Before ASSO.","1 mol",,),("After asso.",1-x,,""(x)/(2)):}`
Total `=1-x+(x)/(2)=1-(x)/(2)`
`THEREFORE""i=(1-x//2)/(1)=1-(x)/(2)`.
Discussion
19.

v1_newFlow

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`i=(1-ALPHA)`
`i=(1+alpha)`
`i=(1-alpha//2)`
`i=(1+alpha//2)`

Solution :`2C_(6)H_(5)COOHhArr(C_(6)H_(5)COOH)_(2)`
For association,
`alpha=((i-1))/((1//n-1))=((i-1))/((1//2-1))`
`-alpha//2=i-1or i=(1-alpha//2)`
Discussion
20.

Benzoic acid to m-nitrobenzylalcohol

Answer»

SOLUTION :
Discussion
21.

Benzoic acid to benzaldehyde

Answer»

Solution :`C_(6)H_(5)COOH UNDERSET("PYRIDINE")overset(SOCl_(2))rarr C_(6)H_(5)COCL underset(underset("(Rosenmund.s reaction)")("Quinoline"))overset(H_(2)//Pd-BaSO_(4))rarr C_(6)H_(5)CHO`
Discussion
22.

Benzoic acid to aniline

Answer»

SOLUTION :
Discussion
23.

Benzoicacid, sorbin acid ,propanoicacid .

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SOLUTION :BENZOICACID, sorbic ACID , propanoicaicd.
Discussion
24.

Benzoic acid reacts with LiAlH_(4) to give

Answer»

Ethylbenzene
Methylbenzene
Phenol
Benzyle alcohol

Solution :
Discussion
25.

Benzoic acid on treatment with HNO_(3) in the presemce of H_(2)SO_(4)gives :

Answer»

m- Nitrobenzoic acid
Nitro benzene
o- Nitrobenzoic acid
m- Sulpho BENZOIC acid.

Solution :
Discussion
26.

Benzoic acid may be prepared by the oxidation of:

Answer»




ANSWER :A::B
Discussion
27.

Benzoic acidmay be preparedby theoxidation of :

Answer»




Discussion
28.

Benzoic acid may be converted to ethyl benzoate by reaction with :

Answer»

ETHYL chloride
Dry HCL `,C_(2)H_(5)OH`
Ethanol
Sodium ethoxide.

Answer :B
Discussion
29.

Benzoic acid may be converted into ethyl benzoate by reaction with

Answer»

SODIUM ethoxide
ethyl chloride
dry HCI, `C_2H_5OH`
ETHANOL

ANSWER :C
Discussion
30.

Benzoic acid is obtained by oxidation of (1)benzaldehyde (2)benzyl alcohol (3) Acetophenone

Answer»

only 1
2,3
1, 3
`1,2,3`

ANSWER :D
Discussion
31.

Benzoic acid is obtained by hydrolysis of

Answer»




ANSWER :A
Discussion
32.

Benzoic acid is obtained by acid hydrolysis of

Answer»

BENZONITRILE
2- phenylethanenitrile
PHENYL isocyanide
2-phenylethaneisonitrile

ANSWER :A
Discussion
33.

Benzoic acid is more stronger than all aliphaticcarboxylic except H - COOH , why ?

Answer»

`C_(6)H_(5) - XOOH` is aromatic ACID
In `C_(6)H_(5) = COOH`, the`- COOH` group is ATTACHED to `sp^(2)` - hydridised atom
resonace stabilization of BENZENE ring
resonance stabilization of benzoate ion.

Answer :B
Discussion
34.

Benzoic acid is less acidic than salicylic acid because of

Answer»

HYDROGEN bond
Inductive effect
Resonance
All of these

Solution :DUE to INTRAMOLECULAR hydrogen BONDING.
Discussion
35.

Benzoic acid is a weaker acid than acetic acid. Is it true or false?

Answer»

SOLUTION :STRONGER
Discussion
36.

Benzoic acid gives benzene on being heated with X and Phenol gives benzene on being heated with Y therefore X and Y are respectively

Answer»

SODALIME and copper
Zinc DUST and Sodium hydroxide
Zinc dust and sodalime
Sodalime and zinc dust

ANSWER :D
Discussion
37.

Benzoic acid does not undergo Friedel-Crafts reaction due to ______of the benzene the _____effect of the -COOH group.

Answer»

SOLUTION :DEACTIVATION, electron-withdrawing.
Discussion
38.

Benzoic acid does not undergo Friedel crafts reaction due ________.

Answer»

RESONANCE in benzene
strong deactivating nature of the CARBOXYL group
due to its higher `pk_(a)` value
All the above

Answer :B
Discussion
39.

Benzoic acid does not undergo _____.

Answer»


ANSWER :Friedel-Craft REACTION
Discussion
40.

Benzoic acid dissolved in benzene shows a molecular weight of:

Answer»

122
61
244
366

Answer :C
Discussion
41.

Benzoic acid completely dimerises is benzene. What will be the vapour pressure os a solution containing 61 g of benzonic acid per 500 g benzene when the vapour pressure of pure benzene at this temperature expermint is 66.6 torr ? What would be vapur pressure in the absence of dimerisation ?

Answer»

Solution :Calculation of Van't haff factor (i)
The association of benzoic acid is represented as: `2(C_(6)H_(5)COOH)hArr(C)(6)H_(5)COOH)_(2)`
Since association is complete, Van't HOFF factor (i)
= `("Normal molar MASS")/("Observed molar mass")=((122g mol^(-1)))/((244g mol^(-1)))=0.5`
Calculation of VAPOUR pressure of the solution `(P_(s))`
`(P_(A)^(@)-P__(S))/P_(S)=i(n_(B))/n_(A)=(ixxW_(B)xxM_(A))/(M_(B)xxW_(A))`
`i=0.5, W_(B)=61g, M_(B)=122g mol^(-1),W_(A)=500g, M_(A)-78g mol^(-1)`
`P_(A)^(@)66.6 torr `
`((66.6 torr-P_(S)))/P_(S)=(0.5xx(61g)xx(78g mol^(-1)))/((122g mol^(-1))xx(500g))=0.039`
`(66.6 torr)-P_(S)=(0.039)xxP_(S)`
`(1.039)xxP_(S)=66.6 torr or P_(S)=((66.6 torr))/((1.039))=64.1 torr`
Calculation of the vapour pressur of solution `(P_(S))` in the ABSENCE of dimersation
In the absence of dimersation i=1, and
`((66.6 torr-P_(S)))/P_(S)=0.039xx2=0.078 , 66.6 torr-P_(S)=(0.078)xxP_(S)`
` P_(S)=((66.6 tor))/((1.078))=61.78 torr`
Discussion
42.

Benzoic acid dissolved in benzene shows

Answer»

its NORMAL MOLECULAR mass
Double of its normal molecular mass
Half of its normal molecular mass
Not definite.

Solution :BENZOIC ACID dimerises in BENZENE.
Discussion
43.

Benzoic acid and carbolic acid can be distiguished by:

Answer»

a.Aqueous `NaHCO_(3)`
b.Netural `FeCl_(3)`
c.Aqueous `NaOH`
d.Aqueous `NH_(3)`

Solution :a. Phenol is also called carbolic acid.
Benzoic acid is more acidic than phenol. So the acid reacts with `NaHCO_(3)` to give `CO_(2)(g)`, while phenol does not react.
b. Acids give buff-coloured precipitate with netural `FeCl_(3)` solution, e.g.,
`3PhCOOH+FeCl_(3) rarr underset("(But coloured ppt.)")underset("(Ferric benzoate)")((PhCOO)_(3)Fe)+3HCl`
`3PhOH+FeCl_(3) rarr underset("(VIOLET colouration)")underset("(Ferric PHENOXIDE)")((PHO)_(3)Fe+3HCl)`
c. Both acid and phenol react with aqueous `NaOH` to give their corresponding SALTS.
`PhCOOH+NaOH rarr PhCOONa`
`PhOH+NaOH rarr PhONa`
Both acid and phenol react with `NH_(3)`.
`PhCOOH+NH_(3) rarr PhCONH_(2) "Benzamide") +H_(2)O`
`PhOH+NH_(30 rarr PhNH_(2) ("Aniline")+H_(2)O`
So the answers are `(a)` and `(b)`.
Discussion
44.

Benzoic acid A underset((ii)Delta)overset((i)NH_3)(to) overset(NaOBr)(to) B overset(NaNO_2//HCl)(to) C'C' is

Answer»

anilinium chloride
O-nitro aniline
BENZENE DIAZONIUM chloride
m-nitro benzoic ACID

Solution :`C_6H_5COOH UNDERSET((II)Delta)overset((i) NH_3) (to) underset( A)(C_6H_5CONH_2 )overset(NaOBr)(to) underset(B)(C_6H_5-NH_2 ) overset(NaNO_2//HCl)(to)C_6H_5-N = N - Cl `
Discussion
45.

Benzoic acetic anhydride on hydrolysis gives

Answer»

BENZOIC acid
acetic acid
MIXTURE of benzoic acid and acetic acid
denzyl ALCOHOL and acetic acid

Answer :C
Discussion
46.

Benzo radical in the following is-

Answer»

`C_(6)H_(5)CH_(2)^(-)`
`C_(6)H_(4) LT`
`C_(6)H_(5) -`

ANSWER :D
Discussion
47.

Benzenesulphonic acid is formed when benzene is treated with

Answer»

COLD dilute `H_(2)SO_(4)`
dilute but hot `H_(2)SO_(4)`
hot and CONCENTRATED `H_(2)SO_(4)`
all of these

ANSWER :C
Discussion
48.

Benzenediazonium salt when simply mixed with KI, gives off ______.

Answer»

`I_(2)`
`N_(2)`
`C_(6)H_(6)`
`Cl_(2)`

Answer :B
Discussion
49.

Benzenediazonium salt on reaction with phenol gives

Answer»

p-hydroxyazobenzene
o-hydroxyazobenzene
m-hydroxyazobenzene
p-aminoazobenzene

Answer :A
Discussion
50.

Benzenediazonium chloride on treatment with KCN in presence of copper powder gives :

Answer»

benzene carbonitrile
aniline
benzene
benzanilide

Solution :SEE PROPERTIES of DIAZONIUM salt (A SECTION)
Discussion