Atomic Structure: MCQ Test (50 questions)

Question 1 of 50

The electronic configuration of an atom is 2, 8, 2. The number of valence electrons in it is-

A10
B12
C8
D2

Question 2 of 50

What is the maximum number of electrons in the N shell?

A2
B8
C18
D32

Question 3 of 50

Who among the following proposed that the atom is indivisible?

ADalton
BBerzelius
CRutherford
Davogado

Question 4 of 50

Stable nuclei (with light A < 10) have-

Ahave approximately equal numbers of neutrons and protons
Bhave more neutrons than protons
Cthere are no neutrons
DThere are no protons

Question 5 of 50

What is the number of protons in a negatively charged atom (anion)?

Agreater than the atomic number of the element
Bless than the atomic number of the element
Cmore than the number of electrons in the atom
Dless than the number of electrons in the atom

Question 6 of 50

The principle that "electrons do not pair up until the vacant orbital available for them is filled" is called-

AHund's law
BPauli's law
CAufbau principle
DHeisenberg's principle

Question 7 of 50

The shape of the nucleus of an atom is-

A10‾⁵ m
B10‾⁹ m
C10.5 m
D10‾¹⁵ m

Question 8 of 50

The maximum number of electrons that an atom of an element can have in its second orbit is-

A8
B32
C18
D2

Question 9 of 50

If an atom of an element has 2 protons, 2 neutrons and 2 electrons, then what will be the mass number of that element?

A2
B4
C6
D8

Question 10 of 50

Rutherford's α-particle experiment first showed that the atom contains-

Aelectron
BProton
Cnucleus
DNeutron

Question 11 of 50

An Indian scientist whose name is associated with a specific fundamental particle is-

ARaman
Bboss
CChandrashekhar
DSaha

Question 12 of 50

Which of the following is a 'temporary' particle?

Aelectron
BProton
CNeutron
DAll of these

Question 13 of 50

Which nuclear particle has no mass and no charge, but has spin?

Aelectron
BProton
CNeutrinos
DMason

Question 14 of 50

The international standard of atomic weight is-

AO-16
BN-14
CC-12
DH-1

Question 15 of 50

The correct relation between energy (E), momentum (p) and velocity (c) of a photon is-

Ap=Ec²
Bp=Ec
Cp=c/E
Dp=E/c

Question 16 of 50

Which one of the following statements regarding the atomic weight of an element is most appropriate?

AThe atomic mass of an element is the sum of the protons and neutrons present in the atom of that element.
BThe atomic weight of an element can vary depending on its mass number.
CThe atomic weight of an element is an integer
DAll atoms of an element have the same atomic weight

Question 17 of 50

The effective radius of an atom is-

A10¯⁶m
B10¯¹⁰m
C10¯¹⁴m
D10¯¹⁵m

Question 18 of 50

What controls the orientation of molecular orbitals?

Aazimuth quantum number
Bspin quantum number
Cmagnetic quantum number
Dprincipal quantum number

Question 19 of 50

The uncertainty principle was formulated by-

AEinstein
BHeisenberg
CRutherford
DPaulie

Question 20 of 50

The discoverer of 'neutrino' is-

AAnderson
BPaulie
CYukawa
DGoldstein

Question 21 of 50

What is the charge on an electron?

A−1.6 X 10‾¹⁹ C
B+ 1.6 X 10‾¹⁹ C
C−1.6 X 10 ¹⁹ C
D+ 1.6 X 10 ¹⁹ C

Question 22 of 50

Which of the following particles has 20 neutrons and 18 electrons?

A₁₇C1ᶾ⁷
B₁₈Arᶾ⁸
C₁₉Kᶾ⁹
D₁₆Sᶾ⁶

Question 23 of 50

The charge on the proton is equal to the charge on the ________.

Aelectron
Balpha particles
CNeutron
DPositron

Question 24 of 50

The atomic number of sodium is 11 and its atomic mass is 23. The number of electrons, neutrons and protons in it will be respectively-

A11, 11, 12
B12, 11, 12
C12, 12, 11
D11, 12, 11

Question 25 of 50

1s², 2s²2p⁶ is the electronic configuration of?

ANa and Ne
BNe and Na⁺
CNe and F
DNa⁺ and F

Question 26 of 50

Who first successfully determined the charge of an electron?

AThomson
BMillikan
CRutherford
DCoulomb

Question 27 of 50

What does the nucleus of a singly ionized carbon atom contain?

A6 protons and 6 neutrons
B5 protons and 6 neutrons
C6 protons, 6 neutrons and 6 electrons
D12 protons, 6 neutrons and 6 electrons

Question 28 of 50

The magnetic quantum number in the context of the molecule of a chemical element is related to-

ABy orientation
Bby frequency
Cby size
Dby rotation

Question 29 of 50

The electronic structure of ₁₃AI²⁷ is-

A2, 8, 2, 1
B2, 8, 3
C2, 8, 1, 2
D3, 8, 2

Question 30 of 50

What are the three basic components of an atom?

Aprotons, neutrinos and ions
Bprotons, neutrons and electrons
Cprotium, deuterium and tritium
Dproton, neutron and ion

Question 31 of 50

The particle that binds the nucleon is-

Aelectron
BPositron
CNeutron
DMason

Question 32 of 50

The number of core electrons in sodium atom is-

A1
B2
C8
D10

Question 33 of 50

How many electrons can be present in the outermost orbit of an atom?

A2
B8
C18
D16

Question 34 of 50

If the number of orbits is expressed by n, then the maximum number of electrons in any orbit will be-

An
Bn²
C2n²
D2nᶟ

Question 35 of 50

When Rutherford bombarded a thin sheet of metal with alpha (α) particles to discover the nucleus, then-

AMost of the alpha particles passed through the metal foil without any emission.
BAll the alpha particles passed through the metal foil.
CMost of the alpha particles are deflected by small angles
DMost of the alpha particles are reflected back.

Question 36 of 50

Which of the following conclusions could not be drawn from Rutherford's α-particle scattering experiment?

AMost of the space in an atom is empty
BThe radius of the atom is approximately 10⁵ times the radius of the nucleus.
CElectrons move in circular paths of constant energy, called orbits
DAlmost all the mass of an atom is in the nucleus

Question 37 of 50

The atomic number of an element is 35 and it has 18 electrons, then the number of protons in it will be-

A17
B18
C20
D15

Question 38 of 50

Who developed the model of atomic structure?

AAlfred Nobel
BFaraday
CBohr and Rutherford
DVolta

Question 39 of 50

Which one of the following is not a part of an atom?

Aelectron
BProton
CNeutron
Dphoton

Question 40 of 50

The discoverer of 'positron' is

AChadwick
BYukawa
CAnderson
DRutherford

Question 41 of 50

The nucleus of a chlorine atom of atomic number 17 and mass number 35 contains-

A18 protons
B18 neutrons
C35 protons
D35 neutrons

Question 42 of 50

The chemical properties of an element depend on-

Aon atomic mass
Bon atomic number
Con the mass number
Don atomic weight

Question 43 of 50

Which one of the following pairs is a particle-antiparticle pair?

Aelectron positron
Bproton neutron
Cphoton – electron
DNeutron - Neutrino

Question 44 of 50

The scattering of which rays can be used to estimate the size of the nucleus?

Aα-particles
Bβ-particles
Cγ-particles
DX-particle

Question 45 of 50

Who first discovered the wave nature of electrons?

AThomson
BDe Broglie
CRutherford
DBohr

Question 46 of 50

'Positron' is the antiparticle of what?

Aelectron
BProton
CNeutron
DMason

Question 47 of 50

Which of the following is the maximum number of electrons that can be present in the M shell?

A2
B8
C18
D32

Question 48 of 50

Which of the following electronic structures is that of sodium ion?

A2, 8, 1
B2, 8
C2, 8, 8
D2, 8, 7

Question 49 of 50

Which of the following atoms does not have a neutron in its nucleus?

ALithium
Bhydrogen
Ctritium
Dhelium

Question 50 of 50

The four quantum numbers of two electrons in an atom cannot be the same. This law is associated with which of the following scientists?

AHund
BPaulie
CFaraday
DArrhenius