Test: NEET 2021 Past Year Paper - NEET MCQ

# Test: NEET 2021 Past Year Paper - NEET MCQ

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## 180 Questions MCQ Test NEET Mock Test Series 2025 - Test: NEET 2021 Past Year Paper

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Test: NEET 2021 Past Year Paper - Question 1

### An infinitely long straight conductor carries a current of 5A as shown. An electron is moving with a speed of 105 m/s parallel to the conductor. The perpendicular distance between the electron and the conductor is 20cm at an instant. Calculate the magnitude of the force experienced by the electron at that instant.

Detailed Solution for Test: NEET 2021 Past Year Paper - Question 1

M.F due to long current carrying wire at 20 cm,

B = 0.5 × 10−5 T
Now,
Force experienced by electron = qVB
Fm = eVB
Fm = 1.6 × 10−19 × 105 × 0.5 × 10−5
= 8 × 10−20 N

Test: NEET 2021 Past Year Paper - Question 2

### A body is executing simple harmonic motion with frequency 'n', the frequency of its potential energy is:

Detailed Solution for Test: NEET 2021 Past Year Paper - Question 2

Given, frequency of SIHM = n
as we know,
∵ In one time period PE become maximum & minimum two time
So, It means frequency of PE is 2n.

Test: NEET 2021 Past Year Paper - Question 3

### A radioactive nucleus undergoes spontaneous decay in the sequencewhere Z is the atomic number of element X. The possible decay particles in the sequence are:

Detailed Solution for Test: NEET 2021 Past Year Paper - Question 3

As we know due to α-decay atomic number decreases by 2 and mass number decreases by 4. Due to β− decay mass number remains unchange and atomic number increases by 1.
Due to  β+ decay mass number remains unchange but atomic number decreares by 1.
So, option (3) is correct option.

Test: NEET 2021 Past Year Paper - Question 4

The escape velocity from the Earth's surface is v. The escape velocity from the surface of another planet having a radius, four times that of Earth and same mass density is :

Detailed Solution for Test: NEET 2021 Past Year Paper - Question 4

As we know escape velocity is given by,

Escape velocity from Earth’s surface = v
Escape velocity from surface of another planet = ?
Rplanet = 4Rearth
Splanet = Searth
So we can write,

It means,

Test: NEET 2021 Past Year Paper - Question 5

The half-life of a radioactive nuclide is 100 hours. The fraction of original activity that will remain after 150 hours would be:

Detailed Solution for Test: NEET 2021 Past Year Paper - Question 5

Given,
T1/2 = 100 hours
t = 150 hours
∵ no. of nuclide remain after n half life, N = N0/2n
∵ 100 hours = 1 half life
150 hours = 1/100 x 150
= 3/2 half life
So, Fraction Remain after 3/2 half life

Test: NEET 2021 Past Year Paper - Question 6

A convex lens 'A' of focal length 20cm and a concave lens 'B' of focal length 5cm are kept along the same axis with a distance 'd' between them. If a parallel beam of light falling on 'A' leaves 'B' as a parallel beam, then the distance 'd' in cm will be :

Detailed Solution for Test: NEET 2021 Past Year Paper - Question 6

Total distance = F1 + F2
= 25 cm

Test: NEET 2021 Past Year Paper - Question 7

A capacitor of capacitance 'C', is connected across an ac source of voltage V, given by V = V0 sin ωt The displacement current between the plates of the capacitor, would then be given by:

Detailed Solution for Test: NEET 2021 Past Year Paper - Question 7

∵ q = CV
And  V = V0 sin ωt
Id = ?
As we know,

Test: NEET 2021 Past Year Paper - Question 8

A small block slides down on a smooth inclined plane, starting from rest at time t = 0 Let Sn be the distance travelled by the block in the interval t = n − 1 to t = n Then, the ratio is:

Detailed Solution for Test: NEET 2021 Past Year Paper - Question 8

Now,
eq (1) divide by (2)

Test: NEET 2021 Past Year Paper - Question 9

A particle is released from height S from the surface of the Earth. At a certain height its kinetic energy is three times its potential energy. The height from the surface of earth and the speed of the particle at that instant are respectively:

Detailed Solution for Test: NEET 2021 Past Year Paper - Question 9

∵ At every pt.
KE + PE =constant
so, (Kε)A + (Pε)A = (kε)B + (Pε)B
0 + mgS = 3(Pε)B + (Pε)B
mgS = 4mgh
h = S/4
Now,
∵ At pt.B -
Kε = 3Pε

Test: NEET 2021 Past Year Paper - Question 10

In a potentiometer circuit a cell of EMF 1.5 V gives balance point at 36cm length of wire. If another cell of EMF 2.5V replaces the first cell, then at what length of the wire, the balance point occurs?

Detailed Solution for Test: NEET 2021 Past Year Paper - Question 10

Given,
E1 = 1.5 V
l1 = 36 cm
E2 = 2.5v
l2 = ?
AS we know,

l2 = 60 cm

Test: NEET 2021 Past Year Paper - Question 11

For a plane electromagnetic wave propagating in x −direction, which one of the following combination gives the correct possible directions for electric field (E) and magnetic field (B) respectively?

Detailed Solution for Test: NEET 2021 Past Year Paper - Question 11

Test: NEET 2021 Past Year Paper - Question 12

Polar molecules are the molecules:

Detailed Solution for Test: NEET 2021 Past Year Paper - Question 12

A polar molecule is a molecule in which one end of the molecule is slightly positive, while the other end is slightly negative. Therefore, these molecules have permanent electric dipole moment.

Test: NEET 2021 Past Year Paper - Question 13

The velocity of a small ball of mass M and density d, when dropped in a container filled with glycerine becomes constant after some time. If the density of glycerine is d/2, then the viscous force acting on the ball will be :

Detailed Solution for Test: NEET 2021 Past Year Paper - Question 13

Fr + Fb = Mg
Fr = Mg-  Fb

Test: NEET 2021 Past Year Paper - Question 14

Match Column - I and Column - II and choose the correct match from the given choices.

Detailed Solution for Test: NEET 2021 Past Year Paper - Question 14

Standard formula for each physical quantity needs to be used.
(A → Q), (B → P), (C → S), (D → R)

Test: NEET 2021 Past Year Paper - Question 15

Water falls from a height of 60m at the rate of 15kg/s to operate a turbine. The losses due to frictional force are 10 \% of the input energy. How much power is generated by the turbine? (g = 10m/s2)

Detailed Solution for Test: NEET 2021 Past Year Paper - Question 15

Change in potential energy of water per second = 15 × g × 60
= 9000 J⁄s
Energy remaining per second after loss = 90% of 9000 J⁄s
= (90/100) x 9000
= 8100 J⁄s = 8.1 kW

Test: NEET 2021 Past Year Paper - Question 16

A lens of large focal length and large aperture is best suited as an objective of an astronomical telescope since :

Detailed Solution for Test: NEET 2021 Past Year Paper - Question 16

The larger the objective, the more light telescope collects and increases the brightness of image and large focal length enhances the magnifying power of the telescope.

Test: NEET 2021 Past Year Paper - Question 17

The electron concentration in an: n-type semiconductor is the same as hole concentration in a p-type semiconductor. An external field (electric) is applied across each of them. Compare the currents in them.

Detailed Solution for Test: NEET 2021 Past Year Paper - Question 17

Electrons effective mass is smaller than holes therefore mobility of electrons is higher than holes and for equal electric field, drift velocity of the electron will be greater compared to holes.
As concentration is also same for both the cases, hence magnitude of current due to electron will be greater compared to that of holes as I = neAv.

Test: NEET 2021 Past Year Paper - Question 18

A nucleus with mass number 240 breaks into two fragments each of mass number 120, the binding energy per nucleon of unfragmented nuclei is 7.6MeV while that of fragments is 8.5MeV. The total gain in the Binding Energy in the process is:

Detailed Solution for Test: NEET 2021 Past Year Paper - Question 18

BE gain = (120 × 8.5) + (120 × 8.5) − (240 × 7.6)
= 2040 − 1824
= 216 MeV

Test: NEET 2021 Past Year Paper - Question 19

A thick current carrying cable of radius 'R' carries current 'I' uniformly distributed across its cross-section. The variation of magneticfield B(r) due to the cable with the distance 'r' from the ax is of the cable is represented by:

Detailed Solution for Test: NEET 2021 Past Year Paper - Question 19

For inside part
J = I/πR2

Test: NEET 2021 Past Year Paper - Question 20

Two charged spherical conductors of radius R1 and R2 are connected by a wire. Then the ratio of surface charge densities of the spheres (σ12) is :

Detailed Solution for Test: NEET 2021 Past Year Paper - Question 20

V1 = V2

Test: NEET 2021 Past Year Paper - Question 21

If E and G respectively denote energy and gravitational constant, then E/G has the dimensions of:

Detailed Solution for Test: NEET 2021 Past Year Paper - Question 21

Dimensional Formulas, Energy,
[E] = M1 L2 T−2
Gravitational constant

Now,

Test: NEET 2021 Past Year Paper - Question 22

A spring is stretched by 5cm by a force 10N. The time period of the oscillations when a mass of 2kg is suspended by it is:

Detailed Solution for Test: NEET 2021 Past Year Paper - Question 22

Spring force, F = kx
Spring constant, k = F/x = 10/0.5 = 200 N⁄m
Time period, T = 2π
T = 2π= 0.2 π = 0.628 s

Test: NEET 2021 Past Year Paper - Question 23

Column - I gives certain physical terms associated with flow of current through a metallic conductor. Column - II gives some mathematical relations involving electrical quantities. Match Column - I and Column - II with appropriate relations.

Detailed Solution for Test: NEET 2021 Past Year Paper - Question 23

A − R, B − S, C − P, D − Q

Test: NEET 2021 Past Year Paper - Question 24

A dipole is placed in an electric field as shown. In which direction will it move?

Detailed Solution for Test: NEET 2021 Past Year Paper - Question 24

F1 = qE1, F2 = qE2
E1 > E2 ⇒ F1 > F2
Hence, net force is towards right and its potential energy will decrease.

Test: NEET 2021 Past Year Paper - Question 25

Consider the following statements (A) and (B) and identify the correct answer.
(A) A zener diode is connected in reverse bias, when used as a voltage regulator.
(B) The potential barrier of p − n junction lies between 0.1V to 0.3V

Detailed Solution for Test: NEET 2021 Past Year Paper - Question 25

(A) is correct while (B) is incorrect because Si diode has barrier potential of 0.7V.

Test: NEET 2021 Past Year Paper - Question 26

A screw gauge gives the following readings when used to measure the diameter of a wire
Circular scale reading : 52 divisions
Given that 1mm on main scale corresponds to 100 divisions on the circular scale. The diameter of the wire from the above data is:

Detailed Solution for Test: NEET 2021 Past Year Paper - Question 26

L.C. = 1/100 mm
= 0.01 mm
Now,
Diameter of wire = 52 × 0.01 = 0.52 mm = 0.052 cm

Test: NEET 2021 Past Year Paper - Question 27

An inductor of inductance L, a capacitor of capacitance C and a resistor of resistance ' R ' are connected in series to an ac source of potential difference ' V ' volts as shown in figure. Potential difference across L,C and R is 40V, 10V and 40V, respectively. The amplitude of current flowing through LCR series circuit is 10√2A. The impedance of the circuit is:

Detailed Solution for Test: NEET 2021 Past Year Paper - Question 27

⇒ z = 50 Ω

Test: NEET 2021 Past Year Paper - Question 28

A parallel plate capacitor has a uniform electric field 'in the space between the plates. If the distance between the plates is 'd' and the area of each plate is 'A', the energy stored in the capacitor is : ∈0 = permittivity of free space)

Detailed Solution for Test: NEET 2021 Past Year Paper - Question 28

Electric energy density u = 1/2 ∈0E2
Volume of the space between plates of Capacitor is Ad.
∴ Energy Stored = Energy density × Volume

Test: NEET 2021 Past Year Paper - Question 29

An electromagnetic wave of wavelength 'λ' is incident on a photosensitive surface of negligible work function. If ' m ' mass is of photoelectron emitted from the surface has de-Broglie wavelength λd, then :

Detailed Solution for Test: NEET 2021 Past Year Paper - Question 29

From Einstein’s equation,
Eincident = ϕ ± KEmax

Test: NEET 2021 Past Year Paper - Question 30

Find the value of the angle of emergence from the prism. Refractive index of the glass is √3.

Detailed Solution for Test: NEET 2021 Past Year Paper - Question 30

No refraction at face AC.
Apply Snell's law at face BC, we get
μ1sini = μ2sinr
√3sin30= 1 × sine
√3/2 = sine
⇒ e = 60

Test: NEET 2021 Past Year Paper - Question 31

The equivalent capacitance of the combination shown in the figure is :

Detailed Solution for Test: NEET 2021 Past Year Paper - Question 31

Redrawing the circuit between A & B

Capacitor 3 can be eliminated and Capacitor 1 & 2 are in parallel.
CAB = C1 + C2
= C + C
= 2C

Test: NEET 2021 Past Year Paper - Question 32

If force [F], acceleration [A] and time [T] are chosen as the fundamental physical quantities. Find the dimensions of energy.

Detailed Solution for Test: NEET 2021 Past Year Paper - Question 32

On comparing powers of [M]
α = 1
On comparing powers of [L]
α + b = 2
⇒ 1 + b = 2
⇒ b = 1
On comparing powers of [T]
−2α − 2b + c = −2
⇒ −2 − 2 + c = −2
⇒ c = 2
[Energy] = [F] [A] [T2]

Test: NEET 2021 Past Year Paper - Question 33

A cup of coffee cools from 90C to 80C in t minutes, when the room temperature is 20C. The time taken by a similar cup of coffee to cool from 80C to 60C at a room temperature same at 20C is:

Detailed Solution for Test: NEET 2021 Past Year Paper - Question 33

From Newton’s Law of cooling,

where, T1 = Initial temperature of body
T2 = Final temperature of body
Ts = Surrounding temperature
t = time taken
For case 1,

Putting the value k from eq. (ℏ),

Test: NEET 2021 Past Year Paper - Question 34

The effective resistance of a parallel connection that consists of four wires of equal length, equal area of cross-section and same material is 0.25 Ω. What will be the effective resistance if they are connected in series?

Detailed Solution for Test: NEET 2021 Past Year Paper - Question 34

Let the resistance of each curve be R

Effective resistance in parallel combination,

RP = R/4
⇒ R = 4RP
⇒ R = 4 x 0.25 = 10 Q

Effective resistance is series combination,
Rs = 4R
⇒ Rs = 4 × 1 = 4 Q

Test: NEET 2021 Past Year Paper - Question 35

The number of photons per second on an average emitted by the source of monochromatic light of wavelength 600 nm, when it delivers the power of 3.3 × 10−3 watt will be : (h = 6.6 × 10−34 Js)

Detailed Solution for Test: NEET 2021 Past Year Paper - Question 35

Energy of each photon, E = hc/λ
⇒ E =
⇒ E = 3.3 × 10−19 J
Number of photons emitted per second, N = P/E

⇒ N = 1016

Test: NEET 2021 Past Year Paper - Question 36

Three resistors having resistances r1, r2 and r3 are connected as shown in the given circuit. The ratio i3/iof currents in terms of resistances used in the circuit is:

Detailed Solution for Test: NEET 2021 Past Year Paper - Question 36

Potential difference between B and C,

Test: NEET 2021 Past Year Paper - Question 37

A point object is placed at a distance of 60 cm from a convex lens of focal length 30 cm. If a plane mirror were put perpendicular to the principal axis of the lens and at a distance of 40 cm from it, the final image would be formed at a distance of :

Detailed Solution for Test: NEET 2021 Past Year Paper - Question 37

Using lens formula,

⇒ v1 = +60 cm Distance of image forwed by lens from Mirror,
d = v1 − 40 = 60 − 40 = 20 cm
The final image will be formed at a distance of 20 cm from Mirror.
Distance of image from lens in 20 cm.
Again, light will refract from lens
Using lens formula,

Hence, the image will be virtual and formed at a distance of 60 from lens or 20 from mirror.

Test: NEET 2021 Past Year Paper - Question 38

For the given circuit, the input digital signals are applied at the terminals A, B and C. What would be the output at the terminal y ?

Detailed Solution for Test: NEET 2021 Past Year Paper - Question 38

Truth table of AND gate for output y1

Truth table of NAND gate for output y2

Truth table of OR gate for output y

Test: NEET 2021 Past Year Paper - Question 39

A step down transformer connected to an ac mains supply of 220V is made to operate at 11 V, 44 W lamp. Ignoring power losses in the transformer, what is the current in the primary circuit?

Detailed Solution for Test: NEET 2021 Past Year Paper - Question 39

Power loss is zero. Hence, output Power is equal to input Power.
So, Input Power, P1 = 44 W
⇒ V1i1 = P1

Test: NEET 2021 Past Year Paper - Question 40

A uniform conducting wire of length 12a and resistance ' R ' is wound up as a current carrying coil in the shape of,
(i) an equilateral triangle of side 'a'.
(ii) a square of side 'a'.
The magnetic dipole moments of the coil in each case respectively are :

Detailed Solution for Test: NEET 2021 Past Year Paper - Question 40

Area of equilateral triangle of side α,

Magnetic moment of each triangle,

12α length of wire will form 4 loops of triangle of side .
Magnetic moment of triangle,

Similarly, magnetic moment of square
M2 = 3 × (Iα2)
= 3Iα2

Test: NEET 2021 Past Year Paper - Question 41

In the product

What will be the complete expression for?

Detailed Solution for Test: NEET 2021 Past Year Paper - Question 41

4ℏ − 20j + 12k = (2i + 4j + 6k) ×

= (4B0 - 6B)i - (2B0 - 6B)j + (2B - 4B)k
4B0 - 6B = 4
2B0 - 6B = 20
2B - 4B = 12 ⇒ B = 6
S0 2B0 - 6(-6) = 20
2B0 = 20 - 36 ⇒ B0 = -8

Test: NEET 2021 Past Year Paper - Question 42

A particle moving in a circle of radius R with a uniform speed takes a time 'I' to complete one revolution. If this particle were projected with the same speed at an angle ' θ ' to the horizontal, the maximum height attained by it equals 4R. The angle of projection, ' θ ', is then given by :

Detailed Solution for Test: NEET 2021 Past Year Paper - Question 42

Test: NEET 2021 Past Year Paper - Question 43

A series LCR circuit containing 5.0 H inductor, 80 μF capacitor and 40 Ω resistor is connected to 230 V variable frequency ac source. The angular frequencies of the source at which power transferred to the circuit is half the power at the resonant angular frequency are likely to be:

Detailed Solution for Test: NEET 2021 Past Year Paper - Question 43

L = 5H, C = 80μF, R = 40ω; ∈rms = 230 V
Half power frequencies,

Here, (40 × 80 × 10−6)2 is negligible.
We get,

Test: NEET 2021 Past Year Paper - Question 44

From a circular ring of mass 'M' and radius 'R'an arc corresponding to a 90 sector is removed. The moment of inertia of the remaining part of the ring about an axis passing through the centre of the ring and perpendicular to the plane of the ring is 'K' times ′MR 2 ′. Then the value of 'K' is :

Detailed Solution for Test: NEET 2021 Past Year Paper - Question 44

mass per unit length of the ring is
λ = M/2πR
∴ Mass of remaining ring is M′ = λ x 3/4 (2πR)
∴ M′ = 3/4 M.

Moment of inertia of remaining part is
I′ = M′R2 = 3/4 MR= KMR2
∴ K = 3/4

Test: NEET 2021 Past Year Paper - Question 45

A uniform rod of length 200cm and mass 500g is balanced on a wedge placed at 40cm mark. A mass of 2kg is suspended from the rod at 20cm and another unknown mass ' m ' is suspended from the rod at 160cm mark as shown in the figure. Find the value of 'm' such that the rod is in equilibrium. (g = 10m/s2)

Detailed Solution for Test: NEET 2021 Past Year Paper - Question 45

Test: NEET 2021 Past Year Paper - Question 46

Right option for the number of tetrahedral and octahedral voids in hexagonal primitive unit cell are:

Detailed Solution for Test: NEET 2021 Past Year Paper - Question 46

In HCP Structure,
Z = 6
Tetrahedral voids = 12
octahedral voids = 06
Hence, the correct answer is (D)

Test: NEET 2021 Past Year Paper - Question 47

Zr(Z ≈ 40) and Hf (Z = 72) have similar atomic and ionic radii because of :

Detailed Solution for Test: NEET 2021 Past Year Paper - Question 47

Zr(40) and Hf (72) have similar atomic and ionic radii because of Lanthanoid Contraction. The 4f orbital offers very poor screening. So, the radius (atomic as well as Ionic) of Zr and Hf are almost the same.

Test: NEET 2021 Past Year Paper - Question 48

For a reaction A →B , enthalpy of reaction is −4.2kJmol−1 and enthalpy of activation is 9.6 kJ mol−1. The correct potential energy profile for the reaction is shown in the option.

Detailed Solution for Test: NEET 2021 Past Year Paper - Question 48

Only option (B) is exothermic. Rest all options are endothermic.

Test: NEET 2021 Past Year Paper - Question 49

Tritium, a radioactive isotope of hydrogen, emits which of the following particles?

Detailed Solution for Test: NEET 2021 Past Year Paper - Question 49

Test: NEET 2021 Past Year Paper - Question 50

The RBC deficiency is deficiency disease of :

Detailed Solution for Test: NEET 2021 Past Year Paper - Question 50

RBC deficiency is because of deficiency of vitamin B12.

Test: NEET 2021 Past Year Paper - Question 51

The molar conductance of NaCl, HCl and CH3COONa at infinite dilution are 126.45, 426.16 and 91.0 S cm2 mol−1 respectively. The molar conductance of CH3COOH at infinite dilution is. Choose the right option for your answer.

Detailed Solution for Test: NEET 2021 Past Year Paper - Question 51

= 91 + 426.16 − 126.45
= 390.71 cm2 mol−1

Test: NEET 2021 Past Year Paper - Question 52

The correct structure of 2,6 - Dimethyl-dec-4-ene is:

Detailed Solution for Test: NEET 2021 Past Year Paper - Question 52

Test: NEET 2021 Past Year Paper - Question 53

The maximum temperature that can be achieved in blast furnace is :

Detailed Solution for Test: NEET 2021 Past Year Paper - Question 53

Furnace can ashine a maximum temperature of around 2200 .

Test: NEET 2021 Past Year Paper - Question 54

Identify the compound that will react with Hinsberg's reagent to give a solid which dissolves in alkali.

Detailed Solution for Test: NEET 2021 Past Year Paper - Question 54

10 Amines react with Hinsberg's reagent (C6 H5S02cl) to form sulphonamides with an acidic Hydrogen.
Hence, these are soluble in alkali.

Test: NEET 2021 Past Year Paper - Question 55

The following solutions were prepared by dissolving 10 g of glucose (C6H12O6) in 250ml of water (P1) , 10 g of urea (CH4 N2O) in 250ml of water (P2) and 10 g of sucrose (C12H22O11) in 250ml of water (P3) . The right option for the decreasing order of osmotic pressure of these solutions is :

Detailed Solution for Test: NEET 2021 Past Year Paper - Question 55

Osmotic pressure (π) = CRT
At same temperature, π ∝ c

Test: NEET 2021 Past Year Paper - Question 56

The major product of the following chemical reaction is:

Detailed Solution for Test: NEET 2021 Past Year Paper - Question 56

Unsymmetrical alkenes undergo anti markovnikov's addition reaction with HBr in the Presence of peroxide

Test: NEET 2021 Past Year Paper - Question 57

Given below are two statements:
Statement I: Aspirin and Paracetamol belong to the class of narcotic analgesics.
Statement II: Morphine and Heroin are non-narcotic analgesics.
In the light of the above statements, choose the correct answer from the options given below.

Detailed Solution for Test: NEET 2021 Past Year Paper - Question 57

Non-addictive analgesics are Known as Non-narcotic analgesics. Aspirin and paracetamol belong to this class. Narcotics are also called opioid pain relievers.. Both morphine and Heroin are belong to this class.

Test: NEET 2021 Past Year Paper - Question 58

The correct sequence of bond enthalpy of ' C −X bond is:

Detailed Solution for Test: NEET 2021 Past Year Paper - Question 58

Bond enthalpy is inversely proportional to the bond length. The bond length order of C-X bond in methyl halides depends on the size of the halogen atom. Bond length order: CH3 − F < CH3 - Cl < CH3Br < CHI
Hence, bond enthalpy order is CH3 - F > CH3 - Cl > CH3 - Br > CH3 - I

Test: NEET 2021 Past Year Paper - Question 59

BF3 is planar and electron deficient compound. Hybridization and number of electrons around the central atom, respectively are :

Detailed Solution for Test: NEET 2021 Past Year Paper - Question 59

The structure of BF3 can be shown as follows,

Three hybrid orbital are required to form BF3. Hence, the hybridisation of Boron is sp2 and the number of electrons around the boron is 6 due to the presence of three B-F bonds

Test: NEET 2021 Past Year Paper - Question 60

Which one among the following is the correct option for right relationship between CP and CV for one mole of ideal gas?

Detailed Solution for Test: NEET 2021 Past Year Paper - Question 60

For one mole of ideal gas ΔH = ΔU + Δ(PV)
= ΔU + Δ(RT)
= ΔU + RΔT
ΔH = CpΔT, ΔU = CvΔT
CpΔT = CvΔT + RΔT
Cp = Cv + R
Cp − CV = R

Test: NEET 2021 Past Year Paper - Question 61

Among the following alkaline earth metal halides, one which is covalent and soluble in organic solvents is :

Detailed Solution for Test: NEET 2021 Past Year Paper - Question 61

Due to the high polarising power of Be2+ ion, its compounds are covalent. Becl2 is readily soluble in organic solvents.

Test: NEET 2021 Past Year Paper - Question 62

An organic compound contains 78 % (by wt.) carbon and remaining percentage of hydrogen. The right option for the empirical formulā of this compound is: [Atomic wt. of C is H is 1]