NEET Minor Test - 4 - NEET MCQ

# NEET Minor Test - 4 - NEET MCQ

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## 180 Questions MCQ Test NEET Mock Test Series 2025 - NEET Minor Test - 4

NEET Minor Test - 4 for NEET 2024 is part of NEET Mock Test Series 2025 preparation. The NEET Minor Test - 4 questions and answers have been prepared according to the NEET exam syllabus.The NEET Minor Test - 4 MCQs are made for NEET 2024 Exam. Find important definitions, questions, notes, meanings, examples, exercises, MCQs and online tests for NEET Minor Test - 4 below.
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NEET Minor Test - 4 - Question 1

### A body of mass 60g experiences a gravitational force of 3.0N, when placed at a particular point. The magnitude of the gravitational field intensity at that point is

Detailed Solution for NEET Minor Test - 4 - Question 1

F = mEG

3 = 60/1000 EG

EG = 50N / kg

NEET Minor Test - 4 - Question 2

### A gravitational field is present in a region and a mass is shifted from A to B through different paths as shown. If W1 W2 and W3 represent the work done by the gravitational force along the respective paths, then:

Detailed Solution for NEET Minor Test - 4 - Question 2
Gravitational force is a conservative force work done by conservative force is path independent.

Hence, ∴ W1 = W2 = W3

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NEET Minor Test - 4 - Question 3

### The ratio of Coulomb's electrostatic force to the gravitational force between an electron and a proton separated by some distance is 2.4 × 1039. The ratio of the proportionality constant, to the Gravitational constant G is nearly (Given that the charge of the proton and electron each =1.6 × 10−19C, the mass of the electron = 9.11 × 10−31kg, the mass of the proton = 1.67×10−27kg ) :

Detailed Solution for NEET Minor Test - 4 - Question 3

NEET Minor Test - 4 - Question 4

A particle of mass ' m ' is projected with a velocity v = kVe (k < 1) from the surface of the earth. (Ve = escape velocity) The maximum height above the surface reached by the particle is

Detailed Solution for NEET Minor Test - 4 - Question 4
given v=kVe

where, k < />

Thus, v < />e

From conservation of mechanical energy,

We know,

NEET Minor Test - 4 - Question 5

The work done to raise a mass m from the surface of the earth to a height h, which is equal to the radius of the earth, is

Detailed Solution for NEET Minor Test - 4 - Question 5
Initial potential energy at earths surface is Ui = −GMm/R

Final potential energy at height h = R

As work done = change in PE

∴ W = Uf − Ui

= GMm /

(∵ GM = gR2)

=

NEET Minor Test - 4 - Question 6

The time period of a geostationary satellite is 24h, at a height 6RE(RE. is radius of earth) from surface of earth. The time period of another satellite whose height is 2.5RE from surface will be,(

Detailed Solution for NEET Minor Test - 4 - Question 6

NEET Minor Test - 4 - Question 7

If the mass of the Sun were ten times smaller and the universal gravitational constant were ten times larger in magnitude, which of the following is not correct?

Detailed Solution for NEET Minor Test - 4 - Question 7
′g′ on the earth will not change.

If universal gravitational constant become term then G′ = 10G

Acceleration due to gravity, ,g = Gm/R2

So, Acceleration due to gravity increases.

NEET Minor Test - 4 - Question 8

Two astronauts are floating in gravitational free space after having lost contact with their spaceship. The two will

Detailed Solution for NEET Minor Test - 4 - Question 8
Since two astronauts are floating in gravitational free space. The only force acting on the two astronauts is the gravitational pull of their masses,

F = Gm1m2,

which is attractive in nature.

Hence they move towards each other.

NEET Minor Test - 4 - Question 9

A satellite of mass m is orbiting the earth (of radius R) at a height h from its surface. The total energy of the satellite in terms of g0, the value of acceleration due to gravity at the earth’s surface, is

Detailed Solution for NEET Minor Test - 4 - Question 9
Total energy of satellite at height h from the earth surface,

Also,

From eqns. (i) and (ii),

NEET Minor Test - 4 - Question 10

The ratio of escape velocity at earth (ve) to the escape velocity at a planet (vp) whose radius and mean density are twice as that of earth is

Detailed Solution for NEET Minor Test - 4 - Question 10
As escape velocity.

NEET Minor Test - 4 - Question 11

A satellite S is moving in an elliptical orbit around the earth. The mass of the satellite is very small compared to the mass of the earth. Then,

Detailed Solution for NEET Minor Test - 4 - Question 11
The gravitational force on the satellite S acts towards the centre of the earth, so the acceleration of the satellite S is always directed towards the centre of the earth.
NEET Minor Test - 4 - Question 12

A black hole is an object whose gravitational field is so strong that even light cannot escape from it. To what approximate radius would earth (mass = 5.98 × 1024kg) have to be compressed to be a black hole?

Detailed Solution for NEET Minor Test - 4 - Question 12
Light cannot escape from a black hole,vesc = c

= 8.86 × 10−3m ≈ 10−2m

NEET Minor Test - 4 - Question 13

Infinite number of bodies, each of mass 2 kg are situated on x-axis at distances 1 m, 2 m, 4 m, 8 m ,..., respectively, from the origin. The resulting gravitational potential due to this system at the origin will be

Detailed Solution for NEET Minor Test - 4 - Question 13
The resulting gravitational potential at the origin O due to each of mass 2 kg located at positions as shown in figure is

=

= -4G

NEET Minor Test - 4 - Question 14

The radius of a planet is twice the radius of earth. Both have almost equal average mass-densities. VP and VE are escape velocities of the planet and the earth, respectively, then

Detailed Solution for NEET Minor Test - 4 - Question 14

Here, Rp = 2RE, ρEP

Escape velocity of the earth, VE

=

Escape velocity of the planet

Divide (i) by (ii), we get

NEET Minor Test - 4 - Question 15

The height at which the weight of a body becomes 1/16th its weight on the surface of earth (radius R), is

Detailed Solution for NEET Minor Test - 4 - Question 15
Acceleration due to gravity at a height h from the surface of earth is

where g is the acceleration due to gravity at the surface of earth and R is the radius of earth.

Multiplying by m (mass of the body) on both sides in (i), we get

∴ Weight of body at height h ,W′ = mg′

Weight of body at surface of earth, W = mg

According to question,W′ = 1/16W

or h/R = 3 or h = 3R

NEET Minor Test - 4 - Question 16

The total mechanical energy of a spring-mass system in simple harmonic motion is E = 1/2mω2A2. Suppose the oscillating particle is replaced by another particle of double the mass while the amplitude A remains the same. The new mechanical energy will

Detailed Solution for NEET Minor Test - 4 - Question 16

Total energy depends on k of spring and amplitude A. It is independent of mass.

NEET Minor Test - 4 - Question 17

A body describes simple harmonic motion with an amplitude of 5 cm, and a period of 0.2 s. Find the acceleration and velocity of the body when the displacement is 3 cm, and when the displacement is zero.

Detailed Solution for NEET Minor Test - 4 - Question 17
Given, amplitude,

A = 5 cm = 0.05 m

Time period,

T= 0.2 s

When the displacement is x = 3 cm = 0.03 m, the acceleration is,

A = −ω2x

Velocity is,

When the displacement is x = 0, acceleration a = −ω2x = 0.

Velocity,

NEET Minor Test - 4 - Question 18

A particle of mass m oscillates with simple harmonic motion between points x1 and x2, the equilibrium position being O. Its potential energy is plotted. It will be as given below in the graph

Detailed Solution for NEET Minor Test - 4 - Question 18
Potential energy of particle performing SHM varies parabolically in such a way that at mean position it becomes zero and maximum at extreme position.
NEET Minor Test - 4 - Question 19

Two simple harmonic motions of angular frequency 100 and 1000 rad s–1 have the same displacement amplitude. The ratio of their maximum acceleration is

Detailed Solution for NEET Minor Test - 4 - Question 19

NEET Minor Test - 4 - Question 20

The displacement of a particle along the x-axis is given by x = asin2ωt. The motion of the particle corresponds to

Detailed Solution for NEET Minor Test - 4 - Question 20

x = asin2ωt

On comparing (1)1 with the standard sinusoidal equation of SHM, we get,

We conclude that the given equation represents the simple harmonic motion of amplitude a/2 and angular frequency 2ω.

NEET Minor Test - 4 - Question 21

The circular motion of a particle with constant speed is

Detailed Solution for NEET Minor Test - 4 - Question 21
In a circular motion particle repeats after equal intervals of time. So particle motion on a circular path is periodic but not simple harmonic as it does not execute to and fro motion about a fixed point.
NEET Minor Test - 4 - Question 22

A body is vibrating in simple harmonic motion. If its acceleration is 12 cm s−2 at a displacement 3 cm, then time period is

Detailed Solution for NEET Minor Test - 4 - Question 22

Here a = 12 cm s−2 at x = 3 cm

In SHM, acceleration a = −ω2x

∴ Magnitude of acceleration a = ω2x

NEET Minor Test - 4 - Question 23

A simple pendulum is released from A shown.

If m and l represent the mass of the bob and Length of the pendulum, the gain kinetic energy at B is

Detailed Solution for NEET Minor Test - 4 - Question 23
Loss of potential energy in coming from A to B

= mgh

= mglcos30° = √3 / 2 mgl

Kinetic energy gained = loss of potential energy

= √3 / 2 mgl

NEET Minor Test - 4 - Question 24

For Simple Harmonic Oscillator, the potential energy is equal to kinetic energy

Detailed Solution for NEET Minor Test - 4 - Question 24
potential energy U and kinetic energy K in SHM are given by

where

m = mass of particle

ω = angular frequency of particle executing SHM

A = amplitude of SHM

X = displacement of particle from mean position

equating both

K = U

hence When a particle executes SHM, there will be two position in each cycle where the PE is equal to KE of the body in SHM

NEET Minor Test - 4 - Question 25

A particle is vibrating in simple harmonic motion with an amplitude of 4 cm. At what displacement from the equilibrium position is its energy half potential and half kinetic?

Detailed Solution for NEET Minor Test - 4 - Question 25
The total energy E of a particle vibrating SHM is given by

The kinetic energy K is given by

where y = displacements of the particle

But,

Hence the kinetic energy is half of the total energy when displacement of the particle is a/√2. Given that a = 4cm.

NEET Minor Test - 4 - Question 26

If the initial tension on a stretched string is doubled, then the ratio of the initial and final speeds of a transverse wave along the string is

Detailed Solution for NEET Minor Test - 4 - Question 26
We know, velocity of transverse wave

NEET Minor Test - 4 - Question 27

In a guitar, two strings A and B made of same material are slightly out of tune and produce beats of frequency 6Hz. When tension in B is slightly decreased, the beat frequency increases to 7Hz. If the frequency of A is 530Hz, the original frequency of B will be

Detailed Solution for NEET Minor Test - 4 - Question 27
Frequency of string,

Frequency ∝ √ Tension

Difference of fA and fB is 6 Hz.

If tension decreases, fB decreases and becomes fB

Now, difference of fA and fB′ = 7Hz (increases) So,fA > fB

fA − fB = 6Hz

⇒ fA = 530Hz

⇒fB = 524Hz (original)

NEET Minor Test - 4 - Question 28

A tuning fork is used to produce resonance in a glass tube. The length of the air column in this tube can be adjusted by a variable piston. At room temperature of 27C two successive resonances are produced at 20cm and 73cm of column length. If the frequency of the tuning fork is 320Hz, the velocity of sound in air at 27C is

Detailed Solution for NEET Minor Test - 4 - Question 28
The velocity of sound in air at 27°C is v = 2(v)[L2 − L1]; where v = frequency of tuning fork and L1, L2 are the successive column length.

∴ v = 2 × 320[73 − 20] × 10−2

= 339.2ms−1 ≈ 339ms−1.

NEET Minor Test - 4 - Question 29

The two nearest harmonics of a tube closed at one end and open at other end are 220 Hz and 260 Hz. What is the fundamental frequency of the system?

Detailed Solution for NEET Minor Test - 4 - Question 29
Nearest harmonics of an organ pipe closed at one end is differ by twice of its fundamental frequency.

∴ 260 − 220 = 2υ, υ = 20 Hz

NEET Minor Test - 4 - Question 30

The second overtone of an open organ pipe has the same frequency as the first overtone of a closed pipe L metre long. The length of the open pipe will be

Detailed Solution for NEET Minor Test - 4 - Question 30

Second overtone of an open organ pipe

=Third harmonic = 3 × υ′0 = 3 × v/2L′

First overtone of a closed organ pipe

= Third harmonic = 3 × υ0 = 3 × v/4L

According to question,

3υ′0 = 3υ0 ⇒3 × v/2L′ = 3 × v/4L

⇒ L′ = 2L

NEET Minor Test - 4 - Question 31

A siren emitting a sound of frequency 800 Hz moves away from an observer towards a cliff at a speed of 15ms−1. Then, the frequency of sound that the observer hears in the echo reflected from the cliff is

(Take velocity of sound in air=330ms−1)

Detailed Solution for NEET Minor Test - 4 - Question 31
Here, frequency of sound emitted by siren,

υ0 = 800Hz

Speed of source, vs = 15ms−1

Speed of sound in air,v = 330ms−1

Apparent frequency of sound at the cliff = frequency heard by observer = υ

Using Doppler's effect of sound

NEET Minor Test - 4 - Question 32

A source of sound S emitting waves of frequency 100 Hz and an observer O are located at some distance from each other. The source is moving with a speed of 19.4 m s'1 at an angle of 60° with the source observer line as shown in the figure. The observer is at rest.

The apparent frequency observed by the observer(velocity of sound in air 330ms−1), is

Detailed Solution for NEET Minor Test - 4 - Question 32

Here, Frequency of source,υ0 = 100 Hz

Velocity of source,vs = 19.4ms−1

Velocity of sound in air,v = 330ms−1

As the velocity of source along the source observer line is vscos60° and the observer is at rest, so the apparent frequency observed by the observer is

NEET Minor Test - 4 - Question 33

The number of possible natural oscillations of air column in a pipe closed at one end of length 85 cm whose frequencies lie below 1250 Hz are

(Velocity of sound = 340ms−1)

Detailed Solution for NEET Minor Test - 4 - Question 33
Fundamental frequency of the closed organ pipe is

υ = v/4L

Here v = 340ms−1,L = 85cm = 0.85m

The natural frequencies of the closed organ pipe will be

υn = (2n − 1)υ = υ, 3υ, 5υ, 7υ, 9υ, 11υ, 13υ,.............

=100Hz, 300Hz, 500Hz, 700Hz, 900Hz, 1100Hz, 1300Hz,.... and so on.

Thus, the natural frequencies lies below the 1250 Hz is 6.

NEET Minor Test - 4 - Question 34

If we study the vibration of a pipe open at both ends, then the following statement is not true.

Detailed Solution for NEET Minor Test - 4 - Question 34
Pressure change will be minimum at both ends.
NEET Minor Test - 4 - Question 35

Two sources of sound placed close to each other, are emitting progressive waves given by y1 = 4sin600πt and y2 = 5sin608πt An observer located near these two sources of sound will hear

Detailed Solution for NEET Minor Test - 4 - Question 35

Given y1 = 4sin600πt, y2 = 5sin608πt

∴ ω1 = 600π or 2πυ1 = 600π or υ1 = 300

A1 = 4

and ω2 = 680π or 2πυ2 = 608π or υ2 = 304

A2 = 5

Number of beats heard per second

= υ2 − υ1 = 304 − 300 = 4

NEET Minor Test - 4 - Question 36

A geostationary satellite is orbiting the earth at a height of 5R above that surface of the earth, R being the radius of the earth. The time period of another satellite in hours at a height of 2R from the surface of the earth is

Detailed Solution for NEET Minor Test - 4 - Question 36
According to Kepler’s third law T2 ∝ r3/2

NEET Minor Test - 4 - Question 37

A particle of mass m is thrown upwards from the surface of the earth, with a velocity u. The mass and the radius of the earth are, respectively, M and R.G is gravitational constant and g is acceleration due to gravity on the surface of the earth. The minimum value of u so that the particle does not return back to earth, is

Detailed Solution for NEET Minor Test - 4 - Question 37
According to law of conservation of mechanical energy

NEET Minor Test - 4 - Question 38

A simple pendulum bob has a mass "m" and length "L". The bob is drawn aside such that the string is horizontal and then it is released. The velocity of the bob while it crosses the equilibrium position is

Detailed Solution for NEET Minor Test - 4 - Question 38

mgL = 1/2mv2

NEET Minor Test - 4 - Question 39

A simple pendulum is made by attaching a 1 kg bob to a 5 m long copper wire. Its period is T. Now, if 1 kg bob is replaced by 10 kg bob, the period of oscillation

Detailed Solution for NEET Minor Test - 4 - Question 39
For simple pendulum T = 2π / lg when weight suspended on elastic wire is increased, its length increases, so time period increases.
NEET Minor Test - 4 - Question 40

A body executes simple harmonic motion. The potential energy (PE), the kinetic energy (KE) and total energy (TE) are measured as function of displacement x. Which of the following statement is true?

Detailed Solution for NEET Minor Test - 4 - Question 40
In S.H.M., at mean position i.e. at x = 0. Kinetic energy will be maximum and the body will be at the lowest potential energy. So, PE will be minimum. Total energy is always constant.
NEET Minor Test - 4 - Question 41

A train moving at a speed of 220ms−1 towards a stationary object, emits a sound of frequency 1000 Hz. Some of the sound reaching the object gets reflected back to the train as echo. The frequency of the echo as detected by the driver of the train is (Speed of sound in air is 330ms−1)

Detailed Solution for NEET Minor Test - 4 - Question 41
Here,

Speed of the train, vT = 220ms−1

Speed of sound in air,v = 330ms−1

The frequency of the echo detected by the driver of the train is

NEET Minor Test - 4 - Question 42

Sound waves travel at 350 m/s through a warm air and at 3500 m/s through brass. The wavelength of a 700 Hz acoustic wave as it enters brass from warm air

Detailed Solution for NEET Minor Test - 4 - Question 42
Here,

When a sound wave travels from one medium to another medium its frequency remains the same,∴ Frequency,υ = v/λ

Since υ remains the same in both the medium

NEET Minor Test - 4 - Question 43

Each of the two strings of length 51.6 cm and 49.1 cm are tensioned separately by 20 N force. Mass per unit length of both the strings is same and equal to 1 g/m. When both the strings vibrate simultaneously the number of beats is

Detailed Solution for NEET Minor Test - 4 - Question 43
l1 = 0.516m, l2 = 0.491m, T = 20N

Mass per unit length, μ = 0.001kg/m

Frequency,

∴ Number of beats = υ1 − υ2 = 7

NEET Minor Test - 4 - Question 44

A wave in a string has an amplitude of 2 cm. The wave travels in the +ve direction of x axis with a speed of 128 m/sec and it is noted that 5 complete waves fit in 4 m length of the string. The equation describing the wave is

Detailed Solution for NEET Minor Test - 4 - Question 44
Amplitude = 2 cm = 0.02 m, v = 128 m/s

∴ y = 0.02sin(7.85x − 1005t)

NEET Minor Test - 4 - Question 45

Two vibrating tuning forks produce waves given by y1 = 4sin500πt and y2 = 2sin506πt Number of beats produced per minute is

Detailed Solution for NEET Minor Test - 4 - Question 45

Y1 = 4sin500πt,Y2 = 2sin506πt

ω1 = 500π = 2πv1 ⇒v1 = 250Hz

ω2 = 506π = 2πv2 ⇒v2 = 253Hz

v = v2 − v1 = 253 − 250 = 3 beats /s

Number of beats per minute =3×60=180.

NEET Minor Test - 4 - Question 46

Equilateral shape has

Detailed Solution for NEET Minor Test - 4 - Question 46
Equilateral or triangular planar shape involves sp2 hybridisation. e.g.,BCl3.
NEET Minor Test - 4 - Question 47

In which one of the following molecules the central atom can be said to adopt sp2 hybridization?

Detailed Solution for NEET Minor Test - 4 - Question 47
BF3 involves sp2 -hybridisation.

NEET Minor Test - 4 - Question 48

Which of the following does not apply to metallic bond?

Detailed Solution for NEET Minor Test - 4 - Question 48
Metallic bonds have electrostatic attraction on all sides and hence do not have directional characteristics.
NEET Minor Test - 4 - Question 49

Which one of the following formulae does not correctly represent the bonding capacities of the two atoms involved?

Detailed Solution for NEET Minor Test - 4 - Question 49

The asterisk ( * ) marked carbon has a valency of 5 and hence this formula is not correct because carbon has a maximum valency of 4.

NEET Minor Test - 4 - Question 50

Which one shows maximum hydrogen bonding?

Detailed Solution for NEET Minor Test - 4 - Question 50
H2O shows maximum H -bonding because each H2O molecule is linked to four H2O molecules through H -bonds.
NEET Minor Test - 4 - Question 51

The complex ion [Co(NH3)6]3+ is formed by sp3d2 hybridisation. Hence the ion should possess

Detailed Solution for NEET Minor Test - 4 - Question 51
According to VSEPR theory, a molecule with 6 bond pairs must be octahedral.
NEET Minor Test - 4 - Question 52

In compound X, all the bond angles are exactly 10928′, X is

Detailed Solution for NEET Minor Test - 4 - Question 52
As all C - Cl bonds are directed towards the corner of a regular tetrahedron
NEET Minor Test - 4 - Question 53

Which structure is linear?

Detailed Solution for NEET Minor Test - 4 - Question 53
CO2 molecule is sp -hybridised and thus it is linear, while CO32− is planar (sp2 -hybridised), SO2 is an angular molecule with sp2 hybridisation and SO42− is tetrahedral (sp3− hybridised )
NEET Minor Test - 4 - Question 54

Which one of the following is the correct order of interactions?

Detailed Solution for NEET Minor Test - 4 - Question 54
The van der Waals" forces are weakest forces and covalent bond is strongest, so the order of interactions is

van der Waals' < H-bonding < dipole-dipole < covalent.

NEET Minor Test - 4 - Question 55

Which of the following molecules has the highest bond order?

Detailed Solution for NEET Minor Test - 4 - Question 55
The bond order of O2+ = 2.5,O22− =1, O2 = 1.5 and that of O2 = 2
NEET Minor Test - 4 - Question 56

Sodium is heated in air at 300oC to form X. It absorbs CO2CO2 and forms Na2CO and Y. Which of the following is Y?

Detailed Solution for NEET Minor Test - 4 - Question 56
When sodium is heated in air at 300°C, it forms sodium peroxide (Na2O2).

This sodium peroxide reacts with CO2 to give Na2CO3 and O2.

NEET Minor Test - 4 - Question 57

Which one of the following is present as an active ingredient in bleaching powder for bleaching action?

Detailed Solution for NEET Minor Test - 4 - Question 57
Active ingredient in bleaching powder for bleaching action is CaOCl2.
NEET Minor Test - 4 - Question 58

Which of the following cannot be used to generate H2?

Detailed Solution for NEET Minor Test - 4 - Question 58
Mg does not react with NaOH.

NEET Minor Test - 4 - Question 59

An aqueous solution of salt 'R' when treated with dil HCl, a colourless gas is given out. The gas so evolved when passed through acidified KMnO4 decolourises KMnO4 solution. The salt 'R' is

Detailed Solution for NEET Minor Test - 4 - Question 59
ince 'R' gives a colourless gas on reaction with dil HCl, so it contains CO32- or SO32- as anion (i.e., CO2 or SO2 is evolved).

Since the gas decolourises acidified KMnO4 solution so it is SO2 and thus the anion present is SO32- i.e., the salt 'R' is Na2SO3 .

NEET Minor Test - 4 - Question 60

Which property of Na2S2O3 makes it useful in photography?

Detailed Solution for NEET Minor Test - 4 - Question 60
Sodium thiosulphate (Na2S2O3), is useful in photography due to its complex formation property. It is used in photography as a fixer since, it dissolves unexposed silver bromide.
NEET Minor Test - 4 - Question 61

KO2 is used in space and submarines because it,

Detailed Solution for NEET Minor Test - 4 - Question 61
KO2 absorbs CO2 and increases O2 concentration, so it is used in space and submarines.
NEET Minor Test - 4 - Question 62

Mixture of MgCl2 and MgO forms a compound which is known as,

Detailed Solution for NEET Minor Test - 4 - Question 62
Mixture of MgCl2 and MgO is called Sorel's cement. One of its form has the formula MgCl2.5Mg(OH)2.8H2O.
NEET Minor Test - 4 - Question 63

Which one of the following substances is used in the laboratory for a fast drying of neutral gases?

Detailed Solution for NEET Minor Test - 4 - Question 63
Anhydrous calcium chloride, is used for drying in laboratories. The crystals of anhydrous calcium chloride have no water. It absorbs water or vapour from other substances and turns to hydrous calcium chloride. So it is used as a drying agent.
NEET Minor Test - 4 - Question 64

Which of the following ions will have the maximum hydration energy?

Detailed Solution for NEET Minor Test - 4 - Question 64
Hydration energies of smaller cations are higher than those of larger cations. Hence, Mg2+ has the maximum hydration energy among the given options.
NEET Minor Test - 4 - Question 65

Beryllium shows diagonal relationship with

Detailed Solution for NEET Minor Test - 4 - Question 65
The elements of the second period show similar properties as the elements of the third period, which are diagonally placed to them.

NEET Minor Test - 4 - Question 66

Gadolinium has a low value of third ionisation enthalpy because of

Detailed Solution for NEET Minor Test - 4 - Question 66

Gd :- [Xe] 4f75d16s2

In case of 3rd ionisation enthalpy electron will be removed from 5d and resultant configuration will be [Xe]4f f that is stable electronic configuration as it will have high exchange energy, hence less energy will be required to remove 3rd electron.

NEET Minor Test - 4 - Question 67

If radius of second Bohr orbit of the He+ion is 105.8pm, what is the radius of third Bohr orbit of Li2+ ion?

Detailed Solution for NEET Minor Test - 4 - Question 67

NEET Minor Test - 4 - Question 68

Given below are two statements:

Statement I: Cr2+ is oxidising and Mn3+ is reducing in nature.

Statement II: Sc3+ compounds are repelled by the applied magnetic field.

In the light of the above statements, choose the most appropriate answer from the options given below:

Detailed Solution for NEET Minor Test - 4 - Question 68

Cr+2: [Ar]3d4

Cr+2 is reducing as its configuration changes from d4 to d3(t2g3)

Mn+3 is oxidising in nature.

Mn+2: [Ar] 3d5 (extra stability)

Statement I is incorrect

Sc+3: [Ar]

diamagnetic - repelled by magnetic field.

Statement (II) is correct.

NEET Minor Test - 4 - Question 69

Which of the following reactions is the metal displacement reaction? Choose the right option

Detailed Solution for NEET Minor Test - 4 - Question 69
• Both reactions (1) and (4) are examples of decomposition reactions.

• Reactions (2) and (3), both are examples of displacement reactions, while reaction (2) is an example of metal displacement reaction.

NEET Minor Test - 4 - Question 70

Identify the incorrect statement.

Detailed Solution for NEET Minor Test - 4 - Question 70
Oxidation state of Cr in CrO42− and Cr2O72− is +6 i.e. oxidation states are same.
NEET Minor Test - 4 - Question 71

Which one of the following ions exhibits d−d transition and paramagnetism as well?

Detailed Solution for NEET Minor Test - 4 - Question 71

In MnO42−, one unpaired electron (n) is present in d -orbital so, d−d transition is possible.

NEET Minor Test - 4 - Question 72

Name the gas that can readily decolourise acidified KMnO4 solution.

Detailed Solution for NEET Minor Test - 4 - Question 72
SO2 readily decolourises pink violet colour of acidified KMnO4 solution.

NEET Minor Test - 4 - Question 73

The reason for greater range of oxidation states in actinoids is attributed to

Detailed Solution for NEET Minor Test - 4 - Question 73
Actinoids have a greater range of oxidation states due to comparable energies of 5f,6d and 7s orbitals. Hence, all their electrons can take part in bond formation.
NEET Minor Test - 4 - Question 74

Which one of the following statements is correct when SO2 is passed through acidified K2Cr2O7 solution?

Detailed Solution for NEET Minor Test - 4 - Question 74

NEET Minor Test - 4 - Question 75

The catalytic activity of transition metals and their compounds is ascribed mainly to

Detailed Solution for NEET Minor Test - 4 - Question 75
The catalytic activity of transition metals and their compounds is ascribed mainly to their ability to adopt variable oxidation states.
NEET Minor Test - 4 - Question 76

The method used to remove temporary hardness of water is