WBJEE Chemistry Test - 10 | 40 Questions MCQ Test WBJEE Sample Papers, Section Wise & Full Mock Tests JEE

QUESTION: 1

Which one of the following is the weakest Lewis base ?

A.
CH₃⁻
B.
NH₂⁻
C.
OH
D.
F⁻

Solution:

QUESTION: 2

The product acetal is produced by reacting alcohol in the presence of dry HCl with

A.
Acetaldehyde
B.
Ketone
C.
Carboxylic acid
D.
Ether

Solution:

QUESTION: 3

Phenols are more acidic than alcohols because

A.
phenoxide ion is stabilised by resonance
B.
phenols are more soluble in polar solvents
C.
phenoxide ions do not exhibit resonance
D.
Alcohols do not lose H atoms at all.

Solution:

QUESTION: 4

Ions of Ca, Ba and Sr precipitate in fifth group as their

A.
Oxides
B.
Sulphates
C.
Carbonates
D.
Sulphides

Solution:

QUESTION: 5

Electrophiles are

A.
electron loving species
B.
electron hating species
C.
nucleus loving reagents
D.
nucleus hating reagents

Solution:

QUESTION: 6

Molisch test is given by

A.
glucose
B.
surcose
C.
fructose
D.
all of these

Solution:

QUESTION: 7

If r is the radius of first orbit, the radius of nth orbit of the H atom will be

A.
r n²
B.
r n
C.
r/n
D.
r²n²

Solution:

QUESTION: 8

Concentrated nitric acid is added before proceeding to test for group III members. This is to

A.
Oxidise any remaining H₂S
B.
Convert ferrous ion into ferric ion
C.
Form nitrates which give granular precipitates
D.
Increase ionisation of ammonium hydroxide

Solution:

QUESTION: 9

The bond order in O₂⁺ is

A.
2
B.
2.5
C.
1.5
D.
3

Solution:

QUESTION: 10

Which among the following is not a state function ?

A.
Internal energy (E)
B.
Free energy (G)
C.
Enthalpy (H)
D.
Work(W)

Solution:

QUESTION: 11

Which of the following favours the backward reaction in a chemical equilibrium?

A.
increasing the concentration of one of the reactants
B.
add negative catalyst
C.
removal of atleast one of the products at regular intervals
D.
increasing the concentration of one or more of the products

Solution:

QUESTION: 12

To calculate the amount of work done in Joules during a reversible isothermal expansion of an ideal gas, the volume must be expressed in

A.
m³only
B.
dm³only
C.
cm³only
D.
any one of them

Solution:

QUESTION: 13

The reaction 2H₂O₂ → 2H₂O + O₂ is, r= k[H₂O₂]

A.
Zero order reaction
B.
First order reaction
C.
Second order reaction
D.
Third order reaction

Solution:

QUESTION: 14

Azo dyes are prepared from

A.
aniline
B.
benzaldehyde
C.
benzoic acid
D.
phenol

Solution:

QUESTION: 15

The IUPAC name of (CH₃)₂CHCH₂CH₂Cl is

A.
1-Chloropentane
B.
1-Chloro-3-methylbutane
C.
2-Methyl-3-chloropropane
D.
None

Solution:

QUESTION: 16

Which of the following is a complex salt?

A.
Fischer's salt
B.
Glauber's salt
C.
Mohr's salt
D.
Micro cosmic salt

Solution:

QUESTION: 17

Which of the following is a carbonate ore?

A.
diaspore
B.
malachite
C.
pyrolusite
D.
cassiterite

Solution:

QUESTION: 18

Which of the following mixture of gases does not obey Dalton's law of partial pressure ?

A.
O₂ and CO₂
B.
N₂ and O₂
C.
Cl₂ and SO₂
D.
CO₂ and He

Solution:

QUESTION: 19

The electronic configuration of group III elements is

A.
ns¹np²
B.
ns¹ np³
C.
ns² np²
D.
ns² np¹

Solution:

QUESTION: 20

Which of the following melts in boiling water?

A.
Gun metal
B.
Monel metal
C.
Wood metal
D.
Bell metal

Solution:

QUESTION: 21

What is the order of basic nature of hydrides of group V elements ?

A.
AsH₃ > SbH₃ > PH₃ > NH₃
B.
NH₃ > SbH₃ > PH₃ > AsH₃
C.
NH₃ > PH₃ > AsH₃ > SbH₃
D.
PH₃ > NH₃ > SbH₃ > AsH₃

Solution:

QUESTION: 22

The H-O-H bond angle in H₂O molecule is

A.
106⁰
B.
120⁰
C.
109^o.28'
D.
94.8^o

Solution:

QUESTION: 23

Isomers of propionic acid are

A.
HCOOC₂H₅ and CH₃COOCH₃
B.
HCOOC₂H₅ and C₃H₇COOCH
C.
CH₃COOCH₃ and C₃H₇COOC
D.
C₃H₇OH and CH₃COOCH₃ and

Solution:

QUESTION: 24

Which of the following is a man-made element ?

A.
C-14
B.
Np
C.
U
D.
Ra

Solution:

QUESTION: 25

If 50 molecules of a polymer contain molecular weight 500 each. 20 molecules contain molecular weight 200 each and 30 molecules contain molecular weight 300 each then their no. average molecular weight of the polymer is

A.
280
B.
380
C.
480
D.
580

Solution:

QUESTION: 26

Synthetic rubber (Neoprene) is

A.
Polyester
B.
Polyamide
C.
Polysaccharide
D.
Poly (halodiene)

Solution:

QUESTION: 27

Which of the following has the same oxidation state as that of Cr in K₂CrO₃

A.
MgCrO₃
B.
Na₂CrO₃
C.
NH₄CrO₃
D.
Both A and B

Solution:

QUESTION: 28

Which one gives carbylamine reaction ?

A.
CH₃NH₂
B.
C₂H₅NO₂
C.
CH₃CONH₂
D.
(CH₃)₂NH

Solution:

QUESTION: 29

In a metal 'M' having BCC arrangement, edge length of the unit cell is 400 pm. The atomic radius of M is

A.
100 pm
B.
141 pm
C.
173 pm
D.
200 pm

Solution:

QUESTION: 30

Consider the following statements about dimethyl cyclohexanes :
1. trans-1,2-dimethylcyclohexane is more stable than the corresponding cis-isomer
2. cis-1,3-dimethylcyclohexane is an optically inactive meso form
3. trans-1,3-dimethylcyclohexane is more stable than the corresponding cis-isomer
4. cis-1,2-dimethylcyclohexane is an unresolvable racemic mixture
Which of the statements given above are correct ?

A.
1,2 and 3
B.
1,2 and 4
C.
1,3 and 4
D.
2 and 4

Solution:

QUESTION: 31

Among the following metal carbonyls, the C ― O bond order is lowest in

A.
[Mn(CO)₆]⁺
B.
[Fe(CO)₅]
C.
[Cr(CO)₆]
D.
[V(CO)₆]⁻

Solution:

An anionic carbonyl complex can delocalise more electron density to antibonding π - orbital (dπ - pπ back -bonding) of CO and thus lower the bond order.

QUESTION: 32

The IUPAC name of [Ni(NH₃)₄] [NiCl₄] is

A.
Tetrachloronickel (II)-tetraamminenickel (II)
B.
Tetraamminenickel (II)-tetrachloronickel (II)
C.
Tetraamminenickel (II)-tetrachloronickelate (II)
D.
Tetrachloronickel (II)-tetraamminenickelate (0)

Solution:

As per the rules, the positive ions (cation) whether simple or complex, is named first followed by the negative ion (anion).

QUESTION: 33

Which of the following will have fastest rate of reaction with Br₂/FeBr₃?

A.
B.
C.
D.

Solution:

QUESTION: 34

In context with the industrial preparation of hydrogen from water gas (CO + H₂) , which of the following is the correct statement ?

A.
CO and H₂ are fractionally separated using differences in their densities .
B.
CO is removed by absorption in aqueous Cu₂Cl₂ solution .
C.
H₂ is removed through occlusion with Pd.
D.
CO is oxidised to CO₂ with steam in the presence of a catalyst followed by absorption of CO₂ in alkali .

Solution:

QUESTION: 35

The bond dissociation energy of B ― F in BF₃ is 646 kJ mol^-1 whereas that of C ― F in CF₄ is 515 kJ mol^-1. The correct reason for higher B ― F bond dissociation energy as compared to that of C ― F is

A.
smaller size of B-atom as compared to that of C-atom .
B.
stronger σ bond between B and F in BF₃ as compared to that between C and F in CF₄ .
C.
significant p π -p π interaction between B and F in BF₃ whereas there is no possibility of such interaction between C and F in CF₄ .
D.
lower degree of p π -p π interaction between B and F in BF₃ than that between C and F in CF₄ .

Solution:

QUESTION: 36

Which aromatic acid(s) among the following is/are stronger acid than simple benzoic acid ?

A.
B.
C.
D.

Solution:

*Multiple options can be correct

QUESTION: 37

The molecules that will have dipole moment are:

A.
2,2 dimethyl propane
B.
trans 2-pentene
C.
cis 3-hexene
D.
2,2,3,3-tetramethyl butane

Solution:

QUESTION: 38

Statements that are true about Wilkinson's catalyst are:

A.
It is a heterogeneous catalyst.
B.
It has dsp² hybridization and is square planar.
C.
It is a homogeneous catalyst.
D.
It has sp³ hybridization with tetrahedral shape.

Solution:

QUESTION: 39

When HCl(g) is passed through a saturated solution of common salt, pure NaCl is precipitated because

A.
HCl is highly soluble in water
B.
the ionic product [ Na⁺ ] [ Cl^-] exceeds its solubility product (K_sp)
C.
the K_sp of NaCl is lowered by the presence of Cl^-ions
D.
HCl causes precipitation

Solution:

QUESTION: 40

Phosphorous pentachloride reacts with

A.
Alcohols
B.
Ketones
C.
Amines
D.
Ethers

Solution:

WBJEE Chemistry Test - 10

40 Questions MCQ Test WBJEE Sample Papers, Section Wise & Full Mock Tests | WBJEE Chemistry Test - 10

Which one of the following is the weakest Lewis base ?

CH₃⁻

NH₂⁻

OH

F⁻

The product acetal is produced by reacting alcohol in the presence of dry HCl with

Acetaldehyde

Ketone

Carboxylic acid

Ether

Phenols are more acidic than alcohols because

phenoxide ion is stabilised by resonance

phenols are more soluble in polar solvents

phenoxide ions do not exhibit resonance

Alcohols do not lose H atoms at all.

Oxides

Sulphates

Carbonates

Sulphides

electron loving species

electron hating species

nucleus loving reagents

nucleus hating reagents

glucose

surcose

fructose

all of these

Oxidise any remaining H₂S

Convert ferrous ion into ferric ion

Form nitrates which give granular precipitates

Increase ionisation of ammonium hydroxide

2

2.5

1.5

3

Internal energy (E)

Free energy (G)

Enthalpy (H)

Work(W)

increasing the concentration of one of the reactants

add negative catalyst

removal of atleast one of the products at regular intervals

increasing the concentration of one or more of the products

Zero order reaction

First order reaction

Second order reaction

Third order reaction

aniline

benzaldehyde

benzoic acid

phenol

1-Chloropentane

1-Chloro-3-methylbutane

2-Methyl-3-chloropropane

None

Fischer's salt

Glauber's salt

Mohr's salt

Micro cosmic salt

diaspore

malachite

pyrolusite

cassiterite

O₂ and CO₂

N₂ and O₂

Cl₂ and SO₂

CO₂ and He

Gun metal

Monel metal

Wood metal

Bell metal

AsH3 > SbH3 > PH3 > NH3

NH3 > SbH3 > PH3 > AsH3

NH3 > PH3 > AsH3 > SbH3

PH3 > NH3 > SbH3 > AsH3

HCOOC₂H₅ and CH₃COOCH₃

HCOOC₂H₅ and C₃H₇COOCH

CH₃COOCH₃ and C₃H₇COOC

AsH₃ > SbH₃ > PH₃ > NH₃

NH₃ > SbH₃ > PH₃ > AsH₃

NH₃ > PH₃ > AsH₃ > SbH₃

PH₃ > NH₃ > SbH₃ > AsH₃