NEET-UG SERIES

Physics

Atoms

40 previous year questions.

Volume: 40 Ques

Yield: High

High-Yield Trend

1

2024

1

2023

2

2021

2

2020

2

2019

1

2016

3

2015

1

2014

2

2012

1

2011

2

2009

1

2008

2

2006

3

2005

3

2003

Chapter Questions
40 MCQs

01

PYQ 1989

easy

physics ID: neet-ug-

The atomic number of silicon is 14. Its ground state electron configuration is

1

2

3

4

02

PYQ 1989

medium

physics ID: neet-ug-

Curie is a unit of

1

energy of gamma rays

2

half-life

3

radioactivity

4

intensity of gamma rays

03

PYQ 1991

medium

physics ID: neet-ug-

In the nucleus of, the number of protons, neutrons and electrons are

1

11,12,0

2

23,12,11

3

12,11,0

4

23,11,12

04

PYQ 1992

medium

physics ID: neet-ug-

In terms of Bohr radius a0, the radius of the second Bohr orbit of a hydrogen atom is given by

1

2

3

4

05

PYQ 1993

easy

physics ID: neet-ug-

Energy released in the fission of a single nucleus is 200 MeV. The fission rate of filled reactor operating at a power level of 5 W is

1

2

3

4

06

PYQ 1993

medium

physics ID: neet-ug-

Which source is associated with a line emission spectrum?

1

Electric fire

2

Neon street sign

3

Red traffic light

4

Sun

07

PYQ 1997

medium

physics ID: neet-ug-

When hydrogen atom is in its first excited level, its radius, is

1

twice

2

half

3

same

4

four times

08

PYQ 1997

medium

physics ID: neet-ug-

Due to earth's magnetic field, the charged cosmic rays particles

1

can never reach the pole

2

can never reach the equator

3

require greater kinetic energy to reach the equator than pole

4

require less kinetic energy to reach the equator than pole.

09

PYQ 1998

medium

physics ID: neet-ug-

Complete the equation for the following fission process

1

2

3

4

10

PYQ 2000

medium

physics ID: neet-ug-

For the given reaction, the particle is:

1

Neutron

2

Anti neutrino

3

Neutrino

4

Proton

11

PYQ 2000

medium

physics ID: neet-ug-

When an electron does transition from to, then emitted line spectrum will be

1

first line of Lyman series

2

second line of Balmer series

3

first line of Paschen series

4

second line of Paschen series.

12

PYQ 2001

hard

physics ID: neet-ug-

If the energy of a hydrogen atom in nth orbit is, then energy in the nth orbit of a singly ionized helium atom will be

1

2

3

4

13

PYQ 2001

medium

physics ID: neet-ug-

Energy is released in nuclear fission is due to

1

Few mass is converted into energy

2

total binding energy of fragments is more than the binding energy of parental element

3

total binding energy of fragments is less than the binding energy of parental element

4

total binding energy of fragments is equal to the binding energy of parental element.

14

PYQ 2003

medium

physics ID: neet-ug-

J.J. Thomson's cathode-ray tube experiment demonstrated that

1

cathode rays are streams of negatively charged ions

2

all the mass of an atom is essentially in the nucleus

3

the of electrons is much greater than the of protons

4

the ratio of the cathode ray particles changes when a different gas is placed in the discharge tube

15

PYQ 2003

easy

physics ID: neet-ug-

The volume occupied by an atom is greater than the volume of the nucleus by a factor of about

1

2

3

4

16

PYQ 2003

hard

physics ID: neet-ug-

A sample of radioactive element has a mass of at an instant The approximate mass of this element in the sample after two mean lives is

1

1.35 g

2

2.50 g

3

3.70 g

4

6.30 g

17

PYQ 2005

medium

physics ID: neet-ug-

In any fission process the ratio

1

equal to 1

2

greater than 1

3

less than 1

4

depends on the mass of the parent nucleus.

18

PYQ 2005

medium

physics ID: neet-ug-

The total energy of an electron in the first excited state of hydrogen is about -3.4eV. Its kinetic energy in this state is:

1

- 3.4 eV

2

- 1.7 eV

3

1.7 eV

4

3.4 eV

19

PYQ 2005

medium

physics ID: neet-ug-

Energy levels A,B and C of a certain atom correspond to increasing values of energy i.e., E A B C. If and are wavelengths of radiations corresponding to transitions C to B,B to A and C to A respectively, which of the following relations is correct ?

1

=

2

=

3

= 0

4

=

20

PYQ 2006

medium

physics ID: neet-ug-

In a discharge tube ionization of enclosed gas is produced due to collisions between :

1

positive ions and neutral atoms / molecules

2

negative electrons and neutral atoms / molecules

3

photons and neutral atoms / molecules

4

neutral gas atoms / molecules

21

PYQ 2006

medium

physics ID: neet-ug-

Ionization potential of hydrogen atom is 13.6 eV. Hydrogen atoms in the ground state are excited by monochromatic radiation of photon energy 12.1 eV. According to Bohr's theory, the spectral lines emitted by hydrogen will be :

1

two

2

three

3

four

4

one

22

PYQ 2008

easy

physics ID: neet-ug-

The ground state energy of hydrogen atom is -13.6 eV. When its electron is in the first excited state, its excitation energy is

1

10.2eV

2

0

3

3.4eV

4

6.8eV

23

PYQ 2009

easy

physics ID: neet-ug-

In a Rutherford scattering experiment when a projectile of charge and mass approaches a target nucleus of charge and mass, the distance of closest approach is . The energy of the projectile is :

1

Directly proportional to

2

Inversely proportional to

3

Directly proportional to mass

4

Directly proportional to

24

PYQ 2009

medium

physics ID: neet-ug-

In the nuclear decay given below the particles emitted in the sequence are

1

2

3

4

25

PYQ 2011

medium

physics ID: neet-ug-

An electron in the hydrogen atom jumps from excited state n to the ground state. The wavelength so emitted illuminates a photosensitive material having work function . If the stopping potential of the photoelectron is, then the value of is

1

2

2

3

3

4

4

5

26

PYQ 2012

medium

physics ID: neet-ug-

An electron of a stationary hydrogen atom passes from the fifth energy level to the ground level. The velocity that the atom acquired as a result of photon emission will be (is the mass of the electron,, Rydberg constant and Planck's constant)

1

2

3

4

27

PYQ 2012

hard

physics ID: neet-ug-

Electron in hydrogen atom first jumps from third excited state to second excited state and then from second excited to the first excited state. The ratio of the wavelengths emitted in the two cases is:

1

2

3

4

28

PYQ 2014

medium

physics ID: neet-ug-

Hydrogen atom in ground state is excited by a monochromatic radiation of = 975 . Number of spectral lines in the resulting spectrum emitted will be

1

3

2

2

3

6

4

10

29

PYQ 2015

medium

physics ID: neet-ug-

Consider orbit of (Helium), using non-relativistic approach, the speed of electron in this orbit will be [given constant, Z = 2 and h (Planck's Constant) =]

1

0.73 m/s

2

3.0 m/s

3

2.92 m/s

4

1.46 m/s

30

PYQ 2015

medium

physics ID: neet-ug-

The number of d-electrons in is not equal to the number of electrons in which one of the following?

1

d-electrons in Fe (Z=26)

2

p-electrons in Ne (Z=10)

3

s-electrons in Mg (Z=12)

4

p-electrons in Cl (Z=17)

31

PYQ 2015

medium

physics ID: neet-ug-

In the spectrum of hydrogen, the ratio of the longest wavelength in the Lyman series to the longest wavelength in the Balmer series is

1

2

3

4

32

PYQ 2016

medium

physics ID: neet-ug-

Given the value of Rydberg constant is, the wave number of the last line of the Balmer series in hydrogen spectrum will be :

1

2

3

4

33

PYQ 2019

medium

physics ID: neet-ug-

-particle consists of:

1

2electrons and 4 protons only

2

2 protons only

3

2 protons and 2 neutrons only

4

2 electrons, 2 protons and 2 neutrons

34

PYQ 2019

medium

physics ID: neet-ug-

The total energy of an electron in an atom in an orbit is . Its kinetic and potential energies arc, respectively:

1

3.4 eV, -6.8 eV

2

3.4 eV. 3.4 eV

3

-3.4 eV, - 3.4 eV

4

-3.4 eV, -6.8 eV

35

PYQ 2020

medium

physics ID: neet-ug-

The total energy of an electron in the stationary orbit of the hydrogen atom can be obtained by

1

2

3

4

36

PYQ 2020

medium

physics ID: neet-ug-

For which one of the following, Bohr model is not valid?

1

Hydrogen atom

2

Singly ionised helium atom

3

Deuteron atom

4

Singly ionised neon atom

37

PYQ 2021

easy

physics ID: neet-ug-

Polar molecules are the molecules:

1

having zero dipole moment

2

acquire a dipole moment only in the presence of electric field due to displacement of charges

3

acquire a dipole moment only when magnetic field is absent

4

having a permanent electric dipole moment

38

PYQ 2021

medium

physics ID: neet-ug-

Polar molecules are the molecules :

1

having a permanent electric dipole moment

2

having zero dipole moment

3

acquire a dipole moment only in the presence of electric field due to displacement of charges

4

acquire a dipole moment only when magnetic field is absent

39

PYQ 2023

easy

physics ID: neet-ug-

The radius of innermost orbit of a hydrogen atom is 5.3x10 -11 m. What is the radius of the third allowed orbit of the hydrogen atom?

1

1.06Å

2

1.59Å

3

4.77Å

4

0.53Å

40

PYQ 2024

medium

physics ID: neet-ug-

The spectral series which corresponds to the electronic transition from the levels n 2 = 5, 6,\dots to the level n 1 = 4 is

1

Pfund series

2

Brackett series

3

Lyman series

4

Balmer series