WBJEE Chemistry Test - 14 | 40 Questions MCQ Test WBJEE Sample Papers, Section Wise & Full Mock Tests JEE

QUESTION: 1

HCN behaves as a very weak acid in aqueous medium whereas it acts as a strong acid in liquid ammonia because :

A.
Electronegativity of oxygen is greater than that of nitrogen
B.
Ionization energy of oxygen is less than that of nitrogen
C.
Proton affinity of water is less than that of ammonia
D.
Dipole moment of water is greater than that of ammonia

Solution:

QUESTION: 2

The compound 'A' when treated with methyl alcohol and few drops of H₂SO₄ give wintergreen smell. The compound 'A' is

A.
Succinic acid
B.
Salicylic acid
C.
Tartaric acid
D.
Oxalic acid

Solution:

QUESTION: 3

When HNO₃ is dropped into the palm and washed with water, it turns yellow. It shows the presence of

A.
NO₂
B.
N₂O
C.
NO
D.
N₂O₃

Solution:

QUESTION: 4

Schiff's reagent gives pink colour with

A.
Acetaldehyde
B.
Acetone
C.
Acetic acid
D.
Methyl acetate

Solution:

QUESTION: 5

The energy librated per mole of H⁺ ion by neutralisation of strong acid and strong base :

A.
depends on which acid and base are involved
B.
depends on the temperature at which reaction occurs
C.
depends upon which catalyst is used
D.
is always constant

Solution:

QUESTION: 6

The maximum number of 90^oangles between bond pair-bond pair of electrons is observed in

A.
dsp²-hybridisation
B.
sp³d-hybridisation
C.
dsp³-hybridisation
D.
sp³d²-hybridisation

Solution:

QUESTION: 7

Potassium chromate solution is added to an aqueous solution of a metal chloride. The precipitate thus obtained are insoluble in acetic acid. These are subjected to flame test, the colour of the flame is

A.
Lilac
B.
Apple green
C.
Crimson red
D.
Golden yellow

Solution:

QUESTION: 8

An example of water soluble vitamin is

A.
vitamin A
B.
vitamin C
C.
vitamin D
D.
vitamin E

Solution:

QUESTION: 9

Which of the following pair of ions have same paramagnetic moment?

A.
Cu⁺², Ti⁺³
B.
Mn⁺², Cu⁺²
C.
Ti⁺⁴, Cu⁺²
D.
Ti⁺³, Ni⁺²

Solution:

QUESTION: 10

The alkyl halide is converted into ethyl alcohol by

A.
addition reaction
B.
substitution reaction
C.
elimination reaction
D.
dehydrohalogenation reaction

Solution:

QUESTION: 11

A chemical reaction is in equilibrium when

A.
formation of product is minimum
B.
reactants are completely transformed into products
C.
rates of forward and backward reactions are equal
D.
equal amounts of reactants and products are present

Solution:

QUESTION: 12

Which of the following pair is wrong?

A.
decomposition of H₂O₂-first order reaction
B.
saponification of CH₃COOC₂H₅ -second order reaction
C.
hydrolysis of CH₃COOCH₃ - pseudo unimolecular reaction
D.
combination of H₂ and Br₂ to give HBr- zero order reaction

Solution:

QUESTION: 13

The reaction is spontaneous if the cell potential is

A.
Positive
B.
Negative
C.
Zero
D.
Infinite

Solution:

QUESTION: 14

The IUPAC name of (CH₃)₃ C - CH = CH₂ is

A.
2,2-Dimethyl but 3-ene
B.
2,2-Dimethyl pent - 3-ene
C.
3,3-Dimethyl but -1-ene
D.
Hex-1-ene

Solution:

QUESTION: 15

Which of the following is the function of aspirin?

A.
analgesic
B.
antiseptic
C.
antipyretic
D.
both A and C

Solution:

QUESTION: 16

When the product of pressure and volume is plotted against pressure for a given amount of the gas, the line obtained is

A.
Parallel to X-axis
B.
Parallel to Y-axis
C.
Linear with positive slope
D.
Linear with negative slope

Solution:

QUESTION: 17

When AgNO₃ is added to a solution of Co(NH₃)₅ Cl₃, the precipitate of AgCl shows two ionizable chloride ions. This means:

A.
Two chlorine atoms satisfy primary valency can one secondary valency
B.
One chloride atom satisfies primary as well as secondary valency
C.
Three chlorine atoms satisfy primary valency
D.
Three chloride atoms satisfy secondary valency

Solution:

QUESTION: 18

The nitride salt of Ca when treated with H₂O gives

A.
N₂
B.
CaO
C.
CaH₂
D.
NH₃

Solution:

QUESTION: 19

Aluminium (III) chloride forms a dimer because

A.
Higher co-ordination can be achieved by Al
B.
Al has high ionisation energy
C.
Al belongs to third group
D.
It can not form a trimer

Solution:

QUESTION: 20

Phosphorus is manufactured by heating in furnace

A.
Bone ash, sodium chlorie and coke
B.
Bone ash, silica and coke
C.
Bone ash, silica and lime
D.
Bone ash, coke and lime stone

Solution:

QUESTION: 21

The principal constitutent of pyrex glass is

A.
Zn
B.
Pb
C.
B
D.
Cl

Solution:

QUESTION: 22

A metal which does not liberate H₂(g) from acids is;

A.
Cu
B.
Fe
C.
Mn
D.
Zn

Solution:

QUESTION: 23

How many structural isomers could be obtained from alkalne C₆H₁₄?

A.
Four
B.
Five
C.
Six
D.
Seven

Solution:

QUESTION: 24

Isotopes of elements were discovered by

A.
Soddy
B.
Curie
C.
Chadwick
D.
Thomson

Solution:

QUESTION: 25

Which of the following will exhibit tautomerism?

A.
(CH₃)₂CNO
B.
(CH₃)₂NH
C.
R₃CNO₂
D.
RCH₂NO₂

Solution:

QUESTION: 26

WHich of the following polymer is an example of fibre?

A.
silk
B.
dacron
C.
nylon-66
D.
all of these

Solution:

QUESTION: 27

Which of the following is a bio-degradable polymer?

A.
PVC
B.
nylon-6
C.
cellulose
D.
polythene

Solution:

QUESTION: 28

In which of the following reaction there is no change in oxidation number

A.
SO₂ + 2H₂S → 2H₂O + 3S
B.
2Na + O₂ → Na₂O₂
C.
Na₂O + H₂SO₄ → Na₂SO₄ + H₂O
D.
4KClO₃ → 3KClO₄ + KCl

Solution:

QUESTION: 29

AB is an ionic solid. If the ratio of ionic radii of A⁺ and B⁻ is 0 .52. What is the coordination number of B⁻

A.
2
B.
3
C.
6
D.
8

Solution:

Ratio r ⁺/r^- = 0.414 - 0.732
Coordination no. is 6.

QUESTION: 30

A pair of diastereoisomers will be formed when :

A.
An optically active acid reacts with an optically active base
B.
An optically inactive base reacts with an optically active acid
C.
An optically active base reacts with the racemic modification of an acid
D.
A racemic modification of a base recats with optically inactive acid

Solution:

QUESTION: 31

The IUPAC name of

A.
4-Hydroxy-1-methylpentanal
B.
4-Hydroxy-2-methylpentanal
C.
3-Hydroxy-2-methylpentanal
D.
3-Hydroxy-3-methylpentanal

Solution:

QUESTION: 32

Which one of the following compounds will be most easily attacked by an electrophile ?

A.
B.
C.
D.

Solution:

QUESTION: 33

The number of stereoisomers possible for a compound of the molecular formula
CH₃― CH ═ CH ― CH (OH) ― Me is

A.
3
B.
2
C.
4
D.
6

Solution:

QUESTION: 34

In the following reaction,

the structure of the major product 'X' is

A.
B.
C.
D.

Solution:

QUESTION: 35

In the following reaction sequence, the correct structures of E, F and G are

(* implies ¹³C labelled carbon)

A.
B.
C.
D.

Solution:

QUESTION: 36

Which statement(s) about conductivity of water is/are correct?

A.
It possesses almost non-conducting nature
B.
It is obtained by distillation of water several times
C.
It is contaminated with little acid
D.
None of these

Solution:

QUESTION: 37

Nitrogen (I) oxide is produced by :

A.
Thermal decomposition of ammonium nitrate .
B.
Disproportionation of N₂O₄.
C.
Thermal decomposition of ammonium nitrite.
D.
Interaction of hydroxylamine and nitrous acid.

Solution:

QUESTION: 38

Sodium sulphate is highly soluble in water, but calcium sulphate is only sparingly soluble because

A.
lattice energy of Na₂SO₄ is less than its hydration energy.
B.
hydration energy of CaSO₄ is less than its lattice energy.
C.
lattice energy of Na₂SO₄ is greater than its hydration energy.
D.
lattice energy of CaSO₄ is less than its hydration energy.

Solution:

QUESTION: 39

Which of the following statements are not correct ?

A.
The standard value of absolute entropy of elementary substances is taken as zero.
B.
Work done in isothermal expansion is greater than that in the adiabatic expansion for same increase in volume
C.
During adiabatic expansion of a real gas, there is no change in the enthalpy of the system
D.
Expansion against vaccum is very large and hence work is also very large

Solution:

QUESTION: 40

Statements that are the true among the following are:

A.
Calcination is the process of heating the ore in excess supply of air below its melting point.
B.
During roasting, the ore is converted into oxides or sulphates.
C.
Zone refining process involves the principle of fractional crystallization.
D.
Zinc is purifies by the method of distillation.

Solution:

WBJEE Chemistry Test - 14

40 Questions MCQ Test WBJEE Sample Papers, Section Wise & Full Mock Tests | WBJEE Chemistry Test - 14

HCN behaves as a very weak acid in aqueous medium whereas it acts as a strong acid in liquid ammonia because :

Electronegativity of oxygen is greater than that of nitrogen

Ionization energy of oxygen is less than that of nitrogen

Proton affinity of water is less than that of ammonia

Dipole moment of water is greater than that of ammonia

The compound 'A' when treated with methyl alcohol and few drops of H₂SO₄ give wintergreen smell. The compound 'A' is

Succinic acid

Salicylic acid

Tartaric acid

Oxalic acid

When HNO₃ is dropped into the palm and washed with water, it turns yellow. It shows the presence of

NO₂

N₂O

NO

N₂O₃

Acetaldehyde

Acetone

Acetic acid

Methyl acetate

depends on which acid and base are involved

depends on the temperature at which reaction occurs

depends upon which catalyst is used

is always constant

Lilac

Apple green

Crimson red

Golden yellow

vitamin A

vitamin C

vitamin D

vitamin E

Cu+2, Ti+3

Mn+2, Cu+2

Ti+4, Cu+2

Ti+3, Ni+2

addition reaction

substitution reaction

elimination reaction

dehydrohalogenation reaction

formation of product is minimum

reactants are completely transformed into products

rates of forward and backward reactions are equal

equal amounts of reactants and products are present

decomposition of H₂O₂-first order reaction

saponification of CH₃COOC₂H₅ -second order reaction

hydrolysis of CH₃COOCH₃ - pseudo unimolecular reaction

combination of H₂ and Br₂ to give HBr- zero order reaction

Positive

Negative

Zero

Infinite

2,2-Dimethyl but 3-ene

2,2-Dimethyl pent - 3-ene

3,3-Dimethyl but -1-ene

Hex-1-ene

analgesic

antiseptic

antipyretic

both A and C

Parallel to X-axis

Parallel to Y-axis

Linear with positive slope

Linear with negative slope

Two chlorine atoms satisfy primary valency can one secondary valency

One chloride atom satisfies primary as well as secondary valency

Three chlorine atoms satisfy primary valency

Three chloride atoms satisfy secondary valency

N₂

CaO

CaH₂

NH₃

Higher co-ordination can be achieved by Al

Al has high ionisation energy

Al belongs to third group

It can not form a trimer

Bone ash, sodium chlorie and coke

Bone ash, silica and coke

Bone ash, silica and lime

Cu⁺², Ti⁺³

Mn⁺², Cu⁺²

Ti⁺⁴, Cu⁺²

Ti⁺³, Ni⁺²