What will be the product of following reaction $$\overset{OH}{|}$$ $$\overset{OH}{|}$$ $$CH_3-C-C-CH_3\xrightarrow[]{H_2SO_4}Q$$ $$\underset{H}{|}$$ $$\underset{H}{|}$$ Q is ___________.

$$CH_3-C-CH_2-CH_3$$ $$\; \; \; \; \;\; \; \; \; \;\; \; \underset{O}{||}$$

$$CH_3-C=CH-CH_3$$ $$\; \; \; \; \;\; \; \; \; \; \underset{OH}{|}$$

MCQ Questions for Class 12 Engineering Chemistry Haloalkanes And Haloarenes Quiz 4

What will be the product of following reaction

$\overset{OH}{|}$

$CH_3-C-C-CH_3\xrightarrow[]{H_2SO_4}Q$

$\underset{H}{|}$

Q is ___________.

0%
$CH_3-C-CH_2-CH_3$
$\; \; \; \; \;\; \; \; \; \;\; \; \underset{O}{||}$
0%
$CH_3-C=CH-CH_3$
$\; \; \; \; \;\; \; \; \; \; \underset{OH}{|}$
0%
Both
0%
None

Explanation

Dehydration reaction takes place with the hydride shift. The product is

$2-Butanone$ .

Consider following three halides:
(I)

$C{H}_{3}-C{H}_{2}-Cl$ ;
(II)

$C{H}_{2}=CH-Cl$ ;
(III)

${C}_{6}{H}_{5}Cl$
Arrange

$C-Cl$ bond length of these compounds in decreasing order.

0%
$I > II > III$
0%
$I > III > II$
0%
$III > II > I$
0%
$II > III > I$

The product in the following reaction is:

$Ph - Cl + {Fe}/{{Br}_{2}} \longrightarrow$ Product

0%
o-bromo-chloro benzene
0%
p-bromo-chloro benzene
0%
both of the above
0%
2,4,6-tribromo chloro benzene

The least reactive chlorine is present in:

0%
Methyl chloride
0%
Allyl chloride
0%
Ethyl chloride
0%
Vinyl chloride

Which of the following compound is optically active?

0%
$CH_3 CH_2 COOH$
0%
$CH_3 CHOH COOH$
0%
$HOOC.CH_2.COOH$
0%
$CH_3.CO.COOH$

Explanation

Chiral compounds / chiral molecules are the one's which generally show optical activity and optical isomers are mirror images called enantiomers.

Chiral compounds are those, that have asymmetric centre.

Option:

$B$

2004079_350645_ans_1f6ab957440547a6bb216863889caf37.jpg

Bond order of

$C-X$ bond is:

0%
$1$
0%
$2$
0%
$0.5$
0%
$0$

Explanation

$\begin{array}{l}\text { Bond order - Actually how many bonds present } \\\text { between two atom is known as Bond order. } \\\text { Bond order }=\dfrac{\text { Number of bonding-Number of antibonding}}{2}\end{array}$

$\stackrel{\text { or }}{\text {bond order is valency of the molecule }}$

$\text{C-X bond order is 1}$

1994130_596878_ans_52e6b109b3ed48ac817868c403ade927.jpg

Which is the correct increasing order of bond length of

$C-X$ bond?

0%
$C-F , C-Cl , C-Br , C-I$
0%
$C-Cl , C-F , C-Cl , C-Br$
0%
$C-Br , C-F , C-Cl , C-I$
0%
$C-Cl , C-F , C-Br , C-I$

Explanation

Increase in size of the atom increases the bond length because of largely sized atom formation of bond takes not easily.

Hence

$C-F<C-Cl<C-Br<C-I$ is the increasing order.

$C-X$ bond is polar because:

0%
$X$ is more electronegative than $C$
0%
$X$ attracts electron cloud to itself
0%
$X$ gains slight negative charge on it and $C$ gains slight positive charge on it
0%
all of these

Explanation

$C-X$ bond is polar because X is more E.N than C. X pulls electron cloud towards itself and X gains negative charge on it and carbon gains slight positive charge.

Which is the correct increasing order of dipole moment of

$C-X$ bond?

0%
$C-F, C-Cl, C-Br, C-I$
0%
$C-Br, C-F, C-Cl, C-I$
0%
$C-Cl , C-F , C-Br , C-I$
0%
$C-I , C-Br , C-F , C-Cl$

Explanation

$\begin{array}{l}\text { Dipole moment- it's occur when there is a } \\\text { separation of charge. They can occur between } \\\text { two ions in ionic bond. The dipole moment is a } \\\text { measure of the polarity of the molecule. }\end{array}$

$C-I>C-Br>C-Cl>C-F$

Which alky halide has maximum density?

0%
$C_3H_7F$
0%
$C_2H_5Cl$
0%
$CH_3Br$
0%
$CH_3I$

Explanation

${ CH }_{ 3 }I$ has the highest molecular weight hence, it is alkyl halide with maximum density.

$(Mol. \ wt.\ of\ { CH }_{ 3 }I)=(Mol.\ wt.\ of\ C)+3\times (Mol.\ wt.\ of\ H)+(Mol.\ wt.\ of\ I)$

$=12+(3\times 1)+127$

$=142$

So, the correct option is

$D$

Which of the following does not give white precipitate when boiled with alcoholic silver nitrate:

0%
allyl chloride
0%
t-butyl chloride
0%
chlorobenzene
0%
benzyl chloride

Consider a compound:

$A-CH_2-Cl$

$A$ can be any group. Select the correct statement(s).

0%
If $A=-NO_2$ , $C-Cl$ bond polarity increases.
0%
If $A=-NO_2$ , $C-Cl$ bond polarity decreases.
0%
If $A=-OCH_3$ , $C-Cl$ bond polarity increases.
0%
If $A=-OCH_3$ , $C-Cl$ bond polarity decreases.

Explanation

If A is Electron withdrawing group then bond polarity C-Cl decreases as a shared pair of electrons is now pulled by two groups hence polarity decreases.

If A is Electron donating group polarity increases.

Both

$-NO_{2}$ and

$-OCH_{3}$ are electron withdrawing groups.

Hence the

$C-Cl$ bond polarity decreases.

Which of the following has least polar

$C-X$ bond?

0%
$H_3C-CH=CH_2-Cl$
0%
$HO-CH=CH_2-Cl$
0%
$O_2N-CH=CH_2-Cl$
0%
$HS-CH=CH_2-Cl$

Explanation

strong electro withdrawing group like $NO_2$ when attach to the compound containing $C-Cl$ bond, it decreases the polarity of $C-Cl$ bond due to the opposite pull of sheared pair of electrons.

which of the following compound is the best starting material for reaction:

With respect to chlorobenzene, which of the following statements is not correct?

0%
$Cl$ is ortho-para directing
0%
$Cl$ exhibits $+M$ effect
0%
$Cl$ is ring deactivating
0%
$Cl$ is meta directing

Explanation

$Cl$ exhibits

$-I$ and

$+M$ effect.

Due to which it is ortho/para directing but ring deactivating.

Option D is correct.

What is the sum of positions assigned to bromine while numbering the Parent Chain in the below compounds ?

0%
$13$
0%
$14$
0%
$15$
0%
$16$

The conversion given can be effected using

0%
${Br}_{2}/C{Cl}_{4}$
0%
${Br}_{2}/{H}_{2}O$
0%
${Br}_{2}/Fe$
0%
${Br}_{2}$ /benzoyl peroxide

When ethyl iodide and propyl iodide react with Sodium in presence of ether they form ?

0%
Only one alkane
0%
Mixture of two alkane
0%
Mixture of three alkane
0%
Mixture of four alkane

Phenylbenzoate when treated with

$Br_{2}/Fe$ gives:

Identify the product Z of the given reaction.

$B\overset { alc.KOH }{ \longleftarrow } C_{ 2 }H_{ 5 }Cl\overset { Zn-Cu }{ \underset { { C }_{ 2 }{ H }_{ 5 }OH }{ \longrightarrow } } A.$
Here A and B are respectively:

0%
$CH_4,C_2H_4$
0%
$C_2H_4,C_2H_6$
0%
$C_2H_6,C_2H_4$
0%
$C_2H_6,CH_4$

The halide which will not react with benzene in presence of anhydrous

$AlCl_{3}$ is

0%
$CH_{3}CHClCH_{3}$
0%
$C_{6}H_{5}CH_{2}Cl$
0%
$C_{6}H_{5}Cl$
0%
$CH_{3}CH_{2}CH_{2}Cl$

An organic molecule necessarily shows optical activity if it:

0%
contains asymmetric carbon atoms
0%
in non polar
0%
is non superimposable on its mirror image
0%
is superimposable on its mirror Image

Which one of the following will not be able to show optical isomerism?

0%
1,2 -Propadiene
0%
2, 3 -Propadiene
0%
sec- Butyl alcohol
0%
2, 3- Butanediol

The major product of the elimination is

0%
0%
$H_2C=CH_2$
0%
$H_2C=CH-CH_3$
0%
none of these

The order of reactivity of alkyl halides in Wurtz reaction is

0%
R-I >R-Br >R-Cl
0%
R-I < R-Br < R-Cl
0%
R-Br > R-I < R- Cl
0%
R-I > R-Cl > R - Br

If dichloromethane (DCM) and water

$\left(\mathrm{H}_{2} \mathrm{O}\right)$ are used for differential extraction, which one of the following statements is correct?

0%
DCM and $\mathrm{H}_{2} \mathrm{O}$ would stay as lower and upper layer respectively in the separating funnel (S.F.)
0%
DCM and $\mathrm{H}_{2} \mathrm{O}$ will be miscible clearly
0%
$\mathrm{DCM}$ and $\mathrm{H}_{2} \mathrm{O}$ would stay as upper and lower layer respectively in the separating funnel (S.F.)
0%
DCM and $\mathrm{H}_{2} \mathrm{O}$ will make trubid/colloidal mixture

Which of the following is/are optically active:-

Which is incorrect reactivity order towards nucleophilic reaction?

$(CH_3)_2C=CH_3 \quad \underset { \overrightarrow { P{ h }_{ 2 }{ O }_{ 2 } } }{ HBr } \quad A\quad \underset { \overrightarrow { Drey\quad Ether } }{ Na } \quad B,\quad \\$

$B$ is:-

0%
$(CH_3)_2CH_2Br$
0%
$(CH_3)_3CBr$
0%
$(CH_3)_3C-C(CH_3)_3$
0%
$(CH_3)_2(CH_2)_2(CH_3)_2$

A enantiomerically pure acid is treated with racemic mixture of an alcohol having one chiral carbon. The ester formed will be

0%
optically active mixture
0%
pure enantiomer
0%
meso compound
0%
racemic mixture

Vinyl cholride is more reactive than allyl chloride.

0%
True
0%
False

statement I : Iodination of methane is carried out in presence of

${ HNO }_{ 3 }$ or

${ HIO }_{ 3 }$
statement II :

${ HNO }_{ 3 }$ or

${ HIO }_{ 3 }$ oxides HI to

${ I }_{ 2 }$ to prevent backwards reactions.

0%
Both statements are correct.
0%
Both statements are incorrect.
0%
statement - I is correct, statement - II is incorrect.
0%
statement - I is incorrect, statement - II is correct.

What is the IUPAC name of the given compound?

0%
2,2 -dibromoethane
0%
3,3 -dibromoethane
0%
1,2 -dibromoethane
0%
1,2- dibromopropane

If isopropyl chloride and ethyl chloride both react with Na in presence of dry ether which alkanes will be obtained?

0%
n-Butane
0%
2-methyl butane
0%
2, 3-Dimethyl butane
0%
All of them

Number of

$C$ atoms which present in vinyl acetylene is

0%
2
0%
3
0%
4
0%
1

Which if the following alkane is not produced when the mixture methyl chloride and ethyl chloride is subjected to wurtz reaction?

0%
Ethane
0%
Propane
0%
n-butane
0%
n-pentane

Which hydrocarbon (molecular mass = 72) would yield three different monochloro derivatives?

0%
n-Pentane
0%
Iso-pentane
0%
n-Hexane
0%
Iso-hexane

Which one of the following will form cyclohexane on reaction with two molecules of Na in ether.

0%
$CH_3CH_2-Br$
0%
0%
$Br-CH_2-CH_2-CH_2-CH_2-CH_2-CH_2-Cl$
0%

Which of the following halides is most reactive in an

${ E }_{ 2 }$ reaction with sodium methoxide

0%
$\left( { CH }_{ 3 } \right) _{ 3 }{ CCH }_{ 2 }I$
0%
$\left( { CH }_{ 3 } \right) _{ 2 }CHCHICH_{ 3 }$
0%
$\left( { CH }_{ 3 } \right) _{ 2 }{ CHCH }_{ 2 }Br$
0%
$\left( { CH }_{ 3 } \right) _{ 2 }{ CHCH }_{ 2 }Cl$

The number of stereoisomers possible for a compound of the molecular formula

$\mathrm { CH } _ { 3 } - \mathrm { CH } = \mathrm { CH } - \mathrm { CH } ( \mathrm { OH } ) \mathrm { Me }$ is

0%
4
0%
6
0%
3
0%
2

Choose the correct statement about the following

0%
Both are chiral and $(I)$ is $'R'$ and $(II)$ is $'S'$
0%
Both have chirality of plane and configuration at $(I)$ is $'R'$ and $(II)$ nd is $'S'$
0%
Both are achiral and possess plane of symmetry
0%
$I$ has higher $pKa$ value for 1st deprotonation than $II$

What happens when chlorobenzene is treated with

$KOH$ ?

0%
Phenol
0%
$KCl$
0%
$Both\ A\ and\ B$
0%
$No\ reaction\ takes\ place$

How will you prepare iodoethane from bromoethane:

0%
$AgI$
0%
$AgI/$ acetone
0%
$NaI$
0%
$NaI/$ acetone

Optical activity is shown by :

0%
Glucose
0%
Fructose
0%
Sucrose
0%
All of these

$C_6H_5CHO+HCN\rightarrow C_6H_5-$

$C_{\mid_OH}^{\mid ^{H}}-CH$
The product would be

0%
A racemate
0%
Optically active
0%
A meso compound
0%
A mixture of diastereomers

Explanation

$C_6H_5CHO+HCN\rightarrow C_6H_5\overset { \underset { | }{ H } }{ \underset { \overset { | }{ OH } }{ C } } -CH$ is optically active.

Which of the following statements are correct about nucleophilic acyl substitution?

0%
$RCOCl$ is more reactive than $RCO{N}_{3}$ (acid azide)
0%
$RCO{N}_{3}$ is more reactive than anhydride
0%
$RCO{N}_{3}$ is less reactive than anhydride
0%
Esters are less reactive than anhydrides but more reactive than amides

Reaction of alkyl halide with metallic sodium in presence of dry ether solution is called:

0%
Gabriels reaction
0%
Friedel-Crafts reaction
0%
Sandmeyers reaction
0%
Wurtz reaction

Explanation

Wurtz reaction: Alkyl halide reacts with

$Na$ in presence of dry ether and alkane forms.

$RX+2Na+RX\rightarrow R-R+2NaX$

Option C is correct.

Ethyl bromide on boiling with alcoholic solutions of sodium hydroxide forms:

0%
ethane
0%
ethylene
0%
methylene
0%
all of these

Explanation

$C_2H_5-Br\xrightarrow{NaOH(alc.)}C_2H_4+HBr$

Product (C) is:

0%
0%
0%
0%
None

Explanation

$Ph-Br + CH_3-Br \xrightarrow{AlCl_3+ Benzene \ as \ solvent} \ Ph-CH_3$

The product is (C) = Toluene

CBSE Questions for Class 12 Engineering Chemistry Haloalkanes And Haloarenes Quiz 4 - MCQExams.com

0:0:1

Practice Class 12 Engineering Chemistry Quiz Questions and Answers

CBSE Questions for Class 12 Engineering Chemistry Haloalkanes And Haloarenes Quiz 4 - MCQExams.com

0:0:1

Practice Class 12 Engineering Chemistry Quiz Questions and Answers

Support mcqexams.com by disabling your adblocker.