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	QPID #4796 (SET 2)		CHEMISTRY NEET DPP Day -11 Subjective
Class/Batch: NEET Crash	Duration: 60 min	Date: 06 Apr,2023	Total Mark:200

Instructions: CHEMISTRY NEET DPP Day -11

CHEMISTRY: HYDROCARBONS, Alcohols, Phenols and Ethers(Hydroxy compounds and Ethers), Hydrocarbons-Alkenes, Hydrocarbons-Alkynes,

Section 1 (Part-A) 35X4=140

#2584203

Mark error

Which one of the following will show the highest pH value ?

1)
m–nitrophenol.
2)
p–nitrophenol.
3)
o–nitrophenol
4)
Both (b) and (c).

Solution:
In case of m^–nitrophenol operational effect of nitrogroup is electron withdrawing inductive effect while in case of b and c, both –R and –I effect are operational.

#2584197

Mark error

In the following sequence of reactions.

$C H_{3} C H_{2} O H \overset{P + I_{2}}{\to} A \to_{e t h e r}^{M g} B \overset{H C H O}{\to} C \overset{H_{2} O}{\to} D$ the compound D is

1)
propanal
2)
butanal
3)
n-butyl alcohol
4)
n-propyl alcohol

Solution:

#2584189

Mark error

The reagent used for dehydration of an alcohol is

1)
phosphorus pentachloride
2)
calcium chloride
3)
aluminium oxide
4)
sodium chloride

Solution:
$C H_{2} = C H_{2} \leftarrow_{650 K}^{A l_{2} O_{3}} C H_{3} C H_{2} O H \to_{525 K}^{A l_{2} O_{3}} C H_{3} C H_{2} O C H_{2} C H_{3}$

#2584175

Mark error

ClCH₂CH₂OH is stronger acid than CH₃CH₂OH because of:

1)
– I effect of Cl increases negative charge on O atom of alcohol
2)
– I effect of Cl disperses negative charge on O atom to produce more stable cation
3)
– I effect of Cl disperses negative charge on O atom to produce more stable anion
4)
None of these

Solution:
ClCH₂CH₂OH is stronger acid than CH₃CH₂OH due to – I effect of Cl.

#2584167

Mark error

Mechanism of acid catalysed hydration reaction involves
(i) Protonation of alkene to form carbocation by electrophilic attack of H₃O⁺
(ii) Nucleophilic attack of water on carbocation.
(iii) Deprotonation to form alcohol.

1)
(i) and (ii)
2)
(i) and (iii)
3)
(i), (ii) and (iii)
4)
(ii) and (iii)

Solution:
The mechanism of the reaction involves the following three steps:
Step 1: Protonation of alkene to form carbocation by
electrophilic attack of H₃O⁺
H₂O + H⁺ $\to$ H₃O⁺

Step 2: Nucleophilic attack of water on carbocation.

Step 3: Deprotonation to form an alcohol.

#2584163

Mark error

Which of the following shows structure of allylic alcohol?
(i) CH₂ =CH- CH₂OH
(ii) CH₂ =CH- OH
(iii) CH₂=CH- CH(CH₃ )OH
(iv) CH₂ =CH- C (CH₃)₂ OH

1)
(i), (iii) and (iv)
2)
(i), (ii) and (iv)
3)
(ii), (iii) and (iv)
4)
(i), (ii), (iii) and (iv)

Solution:
CH₂ = CH -OH represents vinylic alcohol. In vinylic alcohols –OH group is attached to sp² hybridized carbon whereas in allylic alcohols – OH group is attached to sp³hybridized carbon.

#2584127

Mark error

Propene, CH₃CH = CH₂ can be converted into 1-propanol by oxidation. Indicate which set of reagents amongst the following is ideal to effect the above conversion ?

1)
KMnO₄ (alkaline)
2)
Osmium tetraoxide (OsO₄/CH₂Cl₂)
3)
B₆H₆ and alk. H₂O₂
4)
O₃/Zn

Solution:
KMnO₄ (alkaline) and OsO₄ / CH₂Cl₂ are used for hydroxylation of double bond while O₃ /Zn is used for ozonolysis. Therefore, the right option is (c), i.e.,

$3 C H_{3} C H = C H_{2} \overset{B H_{3} i n T H F}{\to} {(C H_{3} C H_{2} C H_{2})}_{3} B \to_{N A O H}^{3 H}$ ₂O₂ 3CH₃CH₂CH₂OH1-propanol + H3BO3

#2580542

Mark error

Which of the following statements are correct ?
(i) The general formula of alkenes is CnH2n.
(ii) Alkenes are also known as paraffins.
(iii) Bond length of C–C double bond in alkene is shorter than C–C single bond in alkane.
(iv) Carbon–Carbon double bond in alkene consists of two sigma bonds.
(v) Alkenes are easily attacked by electrophilic reagent.

1)
(i) and (iv)
2)
(i), (iii) and (v)
3)
(i) and (iii)
4)
(i), (ii), (iv) and (v)

Solution:
For statement (ii), Alkenes are also known as olefins. For statement (iv), Carbon–Carbon double bond in alkene consists of one sigma and one pi bond

#2580533

Mark error

Which of the following statements are correct ?
(i) The rate of reactivity of alkanes with halogens is F2 > Cl2 > Br2 > I2.
(ii) Rate of replacement of hydrogens of alkanes is 3° > 2º > 1°
(iii) Fluorination of alkanes is a very slow process.
(iv) Iodination of alkanes is too violent to be controlled.

1)
(i), (ii) and (iii)
2)
(i) and (ii)
3)
(ii) and (iii)
4)
(i) and (iv)

Solution:
For statement (iii), Fluorination is too violent to be controlled. For statement (iv), Iodination is very slow and a irreversible reaction. It can be carried out in the presence of oxidizing agents like HIO₃ or HNO₃

CH₄+ I₂ $\Rightarrow$ CH₃ I+ HI

5HI+ HIO₃ $\underset{}{\to}$ 3I₂ +3H₂ O

10)

#2580523

Mark error

Which of the following statements are correct regarding structure of methane ?
(i) Methane has tetrahedral structure.
(ii) The bond angle between all H – C – H bonds is 109.5°.
(iii) The carbon atom is sp2 hybridized.
(iv) C – C and C – H bond lengths are 154 pm and 112 pm respectively.

1)
(i), (ii) and (iii)
2)
(i), (iii) and (iv)
3)
(i), (ii) and (iv)
4)
(i), (ii), (iii) and (iv)

Solution:
In methane carbon atom is sp³ hybridized

11)

#2580516

Mark error

Benzene is highly unsaturated but it does not undergo addition reaction because

1)
$π$ -electrons of benzene are delocalised.
2)
cyclic structures do not show addition reaction
3)
benzene is a non-reactive compound
4)
All of the above

Solution:
$π$ -electrons of benzene rings are delocalised throughout the molecule. This makes the molecule very stable. The stability resists breaking of double bonds for addition.

12)

#2580513

Mark error

During the nitration of benzene. In the process of generation of nitronium ion sulphuric acid behaves as a/an ______ and nitric acid behave as a/an _________.

1)
base, acid
2)
acid, base
3)
strong acid, weak acid
4)
weak acid, strong acid

Solution:
In the process of generation of nitronium ion, sulphuric acid serves as an acid and nitric acid as a base.

13)

#2580509

Mark error

The electrophilic substitutions reactions of benzene takes place via
(i) generation of electrophile
(ii) generation of nucleophile
(iii) formation of carbocation intermediate
(iv) removal of proton from the carbocation intermediate

1)
(i), (iii) and (iv)
2)
(ii), (iii) and (iv)
3)
(i) and (iv)
4)
(ii) and (iv)

Solution:
According to experimental evidences, electrophilic substitution reactions are supposed to proceed via the following three steps:
(1) Generation of the electrophile
(2) Formation of carbocation intermediate
(3) Removal of proton from the carbocation intermediate

14)

#2580503

Mark error

AlCl₃acts as ________ in Friedel-Crafts reaction

1)
nucleophile
2)
electrophile
3)
free radical
4)
intermediate

Solution:
Friedel- Craft reaction occurs in presence of an attacking reagent which is an electrophile (AlCl₃).

15)

#2580498

Mark error

Benzene on reaction with ozone forms __________.

1)
2 molecules of aldehyde and 1 molecule of ketone
2)
2 molecules of ketone and 1 molecule of aldehyde
3)
triozonide
4)
hexaozonide

Solution:

16)

#2580476

Mark error

Benzene can be obtained in the reaction

1)
Ethene + 1, 3-butadiene
2)
Trimerisation of ethyne
3)
Reduction of PhCHO
4)
All of these

Solution:
Benzene can be obtained by polymerisation of acetylene

17)

#2580453

Mark error

Catalytic hydrogenation of benzene gives

1)
xylene
2)
cyclohexane
3)
benzoic acid
4)
toluene

Solution:

18)

#2580436

Mark error

The product A is

1)
Benzene
2)
Benzaldehyde
3)
Toluene
4)
Benzoic acid

Solution:
This is an example of decarboxylation reaction

19)

#2580421

Mark error

Aromatic compounds burn with sooty flame because

1)
they have a ring structure of carbon atoms
2)
they have a relatively high percentage of hydrogen
3)
they have a relatively high percentage of carbon
4)
they resist reaction with oxygen of air

Solution:
They have a relatively high percentage of carbon

20)

#2580419

Mark error

The benzene molecule contains

1)
6 sp²hybrid carbons
2)
3 sp² hybrid carbons
3)
6 sp³ hybrid carbons
4)
3 sp³ hybrid carbons

Solution:
In the benzene molecule all the six carbons are sp2 hybridised as each C has one double bond.

21)

#2580403

Mark error

Which of the following catalyst is used for the following conversion ?

1)
Platinized Asbestos
2)
Red hot iron tube
3)
Platinized Nickel
4)
Iron-molybdenum

Solution:
Red hot iron tube

22)

#2580394

Mark error

1)
HBr, Br₂, CH₃COCH_3, CH₃CHO
2)
Br₂, HBr, CH₃COCH₃, CH₃CHO
3)
HBr, HBr, C_H3COCH_3, CH₃CHO
4)
Br₂, HBr, CH₃CH₂CHO, CH₃CHO

Solution:
Br₂, HBr, CH₃COCH₃, CH₃CHO

23)

#2580383

Mark error

Which of the following reaction is shown by alkynes ?

1)
Addition
2)
Substitution
3)
Polymerization
4)
All of these

Solution:
Addition – CH $\equiv$ CH + 3H₂ $\overset{N i}{\to}$ CH₃ - CH₃

Substitution – CH $\equiv$ CH+ Na $\underset{}{\to}$ $C H \equiv C^{-} N a^{+} + \frac{1}{2} H_{2}$

Polymerization –

$3 C H \equiv C H \to_{p o l y m e r i z a t i o n}^{h o t c u t u b e} C_{6} H_{6} b e n z e n e$

24)

#2580356

Mark error

Which of these will not react with acetylene?

1)
NaOH
2)
Ammonical AgNO₃
3)
Na
4)
HCl

Solution:
Acetylene reacts with the other three as:

25)

#2580351

Mark error

Which of the following will be the final product when C₂H₂ reacts with HCl

1)
2)
3)
4)
None of these

Solution:
CH $\equiv$ CH+ HCl $\underset{}{\to}$ CH₂ = CH- Cl $\overset{H c l}{\to}$

26)

#2580342

Mark error

Which one of the following has the minimum boiling point ?

1)
1-Butene
2)
1-Butyne
3)
n- Butane
4)
Isobutane

Solution:
Among isomeric alkanes, the straight chain isomer has higher boiling point than the branched chain isomer. The greater the branching of the chain, the
lower is the boiling point. Further due to the presence of $π$ electrons, these molecules are slightly polar and hence have higher boiling points than the
corrosponding alkanes.

27)

#2580313

Mark error

The correct order towards bond length is

1)
C - C < C = C < C $\equiv$ C
2)
C $\equiv$ C < C = C < C - C
3)
C = C < C $\equiv$ C < C - C
4)
C = C < C - C < C $\equiv$ C

Solution:

28)

#2580288

Mark error

The acetylene molecule contains :

1)
5 sigma bonds
2)
4 sigma and 1 pi bonds
3)
3 sigma and 2 pi bonds
4)
2 sigma and 3 pi bonds

Solution:
Acetylene molecule can be represented as,

So, it contains 3 $σ$ and 2 $π$ bonds

29)

#2580257

Mark error

The IUPAC name of the compound CH₃CH = CHC $\equiv$ CH is

1)
Pent-l-yn-3-ene
2)
Pent-4-yn-2-ene
3)
Pent-3-en-1-yne
4)
Pent-2-en-4-yne

Solution:
When both double and triple bonds are present, then
triple bond is considered as the principal group.
CH₃ - CH = CH- C $\equiv$ CH

5 4 3 2 1

30)

#2580245

Mark error

The test for unsaturation is confirmed by the decolourisation of which of the following

1)
Iodine water
2)
CuSO₄solution
3)
Bromine water
4)
All of these

Solution:
By adding bromine water to a solution, if the colour of bromine water decolourise then the compound is unsaturated. This is a confirmatory test for unsaturation.

31)

#2580229

Mark error

The reaction of HI with CH3 – CH = CH2 at 400°C yields :

1)
CH₂ I – CH = CH₂
2)
CH₃ – CHI – CH₃
3)
CH₃ – CH₂ – CH₂ I
4)
CH₂I – CH₂ – CH₂I

Solution:
When unsymmetrical unsaturated hydrocarbon reacts with unsymmetrical reagent, then negative part of reagents attacks that carbon which has less H-atom.
[Markownikoff's rule]

32)

#2580226

Mark error

Ethylene reacts with alkaline KMnO₄ to form

1)
Oxalic acid
2)
HCHO
3)
Ethyl alcohol
4)
Glycol

Solution:

33)

#2580215

Mark error

In the following sequence of reactions, the alkene affords the compound ‘B’

The compound B is

1)
CH₃CH₂CHO
2)
CH₃COCH₃
3)
CH₃CH₂COCH₃
4)
CH₃CHO

Solution:
Completing the sequence of given reactions,
CH3 – CH= CH- CH3 $\overset{O_{3}}{\to}$

Thus ‘B’ is CH₃CHO Hence (d) is correct answer

34)

#2580136

Mark error

Ethyl alcohol is heated with conc. H₂SO₄. The product formed is :

1)
2)
C₂H₆
3)
C₂H₄
4)
C₂H₂

Solution:
C₂H ₅OH $\to_{K M n O_{4}}^{c o n c . H_{2} S O_{4}}$ C₂ H₄ + H₂O

Note : If ethyl alcohol is taken in excess and the reaction is carried out at a temperature of 433-443 K diethyl ether is formed.

2C₂ H₅ OH $\to_{433 - 443 K}^{c o n c . H_{2} S O_{4}}$ C₂H₅OC₂H₅ +H₂O

35)

#2580125

Mark error

Ethyl bromide gives ethylene when reacted with –

1)
ethyl alcohol
2)
dilute H₂SO₄
3)
aqueous KOH
4)
alcoholic KOH

Solution:
CH ₃- CH₂- Br+KOH $\underset{}{\to}$ CH ₂ = CH ₂ + KBr + H₂O

Section 2 (Part-B) 15X4=60

36)

#2583977

Mark error

An ether is more volatile than an alcohol having the same molecular formula. This is due to

1)
dipolar character of ethers
2)
alcohols having resonance structures
3)
inter-molecular hydrogen bonding in ethers
4)
inter-molecular hydrogen bonding in alcohols

Solution:
Due to inter-molecular hydrogen bonding in alcohols boiling point of alcohols is much higher than ether.

37)

#2583968

Mark error

Ethanol and dimethyl ether form a pair of functional isomers. The boiling point of ethanol is higher than that of dimethyl ether, due to the presence of

1)
H-bonding in ethanol
2)
H-bonding in dimethyl ether
3)
CH₃ group in ethanol
4)
CH₃ group in dimethyl ether

Solution:
Due to H-bonding, the boiling point of ethanol is much higher than that of the isomeric diethyl ether.

38)

#2583947

Mark error

Denaturation of alcohol is the

1)
mixing of CuSO₄ (a foul smelling solid) and pyridine (to give the colour) to make the commercial alcohol unfit for drinking
2)
mixing of CuSO₄ (to give the colour) and pyridine (a foul smelling solid) to make the commercial alcohol unfit for drinking
3)
mixing of Cu(OAc)₂and ammonia to make the commercial alcohol unfit for drinking
4)
mixing of Cu(OAc)₂ and pyridine to make the commercial alcohol unfit for drinking

Solution:
The commercial alcohol is made unfit for drinking by mixing in it some copper sulphate (to give it colour) and pyridine (a foul smelling liquid). It is known as denaturation of alcohol.

39)

#2583941

Mark error

Widespread deaths due to liquor poisoning occurs due to

1)
presence of carbonic acid in liquor
2)
presence of ethyl alcohol in liquor
3)
presence of methyl alcohol in liquor
4)
presence of lead compounds in liquor

Solution:
Due to presence of methyl alcohol in liquor.

40)

#2583939

Mark error

Tonics in general contain

1)
Ether
2)
Methanol
3)
Ethanol
4)
Rectified spirit

Solution:
Tonics contain ethyl alcohol.

41)

#168190

Mark error

In the above reaction x is

1)
HNO₃
2)
O₂
3)
O₃
4)
KMnO₄

Solution:

42)

#166134

Mark error

The major product in the following reaction is:

Solution:
Alkenes are more reactive than alkynes and follows markonikov’s addition

43)

#166120

Mark error

The major product in the following reaction:

$R - C \equiv C - {R^|} + {H_2}\xrightarrow{{Na/liqN{H_3}}}?$

Solution:
With Birch catalyst – Trans product is obtained (Controlled reduction)

44)

#151384

Mark error

The final product in following sequence of reaction is

$CH \equiv CH\xrightarrow{{NaN{H_2}}}A\xrightarrow{{C{H_3}Br}}B,$

1)
$C{H_2} = CH - CH = C{H_2}$
2)
$HC \equiv C - C{H_3}$
3)
$C{H_2} = CH - C{H_3}$
4)
$C{H_3} - C{H_2} - C{H_3}$

Solution:
$HC \equiv C - C{H_3}$

45)

#151213

Mark error

Cyclohexene on reaction with OsO₄ followed by reaction with NaHSO₃ gives

1)
𝑐𝑖𝑠 − diol
2)
𝑡𝑟𝑎𝑛𝑠 − diol
3)
Epoxy
4)
Alcohol

Solution:
𝑐𝑖𝑠 − diol

46)

#151019

Mark error

Addition of HBr to propylene in presence of benzoyl peroxide, follows

1)
Markownioff’s rule
2)
Baeyer’s rule
3)
Carbanion mechanism
4)
𝑎𝑛𝑡𝑖-Markownioff’s rule

Solution:
𝑎𝑛𝑡𝑖-Markownioff’s rule

47)

#150983

Mark error

A gas formed by the action of alcoholic KOH on ethyl iodide, decolourises alkaline KMnO₄. The gas is

1)
C₂H₆
2)
CH₄
3)
C₂H₂
4)
C₂H₄

Solution:
C₂H₄

48)

#150940

Mark error

Following compound is treated with NBS Compound formed A is

Solution:

49)

#150916

Mark error

Ethylene reacts with 1% alkaline KMnO₄ to form

1)
Oxalic acid
2)
Ethylene glycol
3)
Ethyl alcohol
4)
HCHO

Solution:
Ethylene glycol

50)

#150893

Mark error

Correct statement about 1,3-dibutene

1)
Conjugated double bonds are present
2)
Reacts with HBr
3)
Forms polymer
4)
All of the above

Solution:
All of the above

QPID #4796 (SET 2)

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