Home
MCQS
Chemistry MCQ Quiz Hub
Chemistry MCQ Question - Atomic Structure
Choose a topic to test your knowledge and improve your Chemistry skills
1. All of the following were theorized by Bohr in his description of the atom except
Angular momentum of electrons in multiples of h/2?
Electrons revolve in discrete circular orbits
Energy of each electron is directly proportional to n2
Electrons radiate energy continuously in a given orbit.
2. The letters s p d and f are used to represent which quantum numbers
Principal
Azimuthal
Magnetic
Spin
3. The magnetic quantum number (QN) has its values determined directly by the value of
Principal (QN)
Azimuthal (QN)
Spin (QN)
Both a & b
4. The atomic number of an element having maximum number of unpaired electrons in p-subshell is
7
10
12
16
5. The maximum number of electron in a sub shell with ? = 3fs
6
10
14
18
6. Radius of the third shell of H-atom is
5.761 A?
4.761 A?
6.671 A?
3.716 A?
7. When an atom absorbs energy the lines in the spectrum will appear which are
Brighter
Darker
Colourless
Hard to locate
8. Colour of fluorescene produced by cathode rays depends upon
Temperature
Pressure
Volume
Composition of glass
9. Which one is not true about cathode rays?
9.11x10-31 Kg
Cast shadow
Heat up the platinum foil
Cannot ionize
10. Positive rays are produced
By burning of gas
By cooling of the gas
By the bombardment of cathode rays on gas molecules
From anode like cathode rays produced from cathode
11. A fast moving neutron can eject from nitrogen
? = rays
? = rays
? = rays
electrons
12. Rutherfords planet like structure was defective and unsatisfactory because
Moving e- accelerate towards the nucleus
Continuous spectrum
behavior of electron remain unexplained
all
13. The relationship between energy of a photon of light and its frequency is given by
de-Broglie duel nature of matter
Bohrs model
Plancks Quantum theory
Rutherfords atomic model
14. Splitting of spectral lines when atom is subjected to magnetic field is called
Zeemans effect
Starks effect
Photo electric effect
Compton effect
15. The velocity of the photon
Is independent of wavelength
Depends upon source
Depends upon its frequency
Equals to the square of amplitude
16. Which one of the following explain the shape of orbitals
Principal of quantum number
Azimuthal quantum number
Magnetic quantum number
Spin quantum number
17. Atom cannot be divided into simple unitstheorized by
Rutherford
Dalton
Bohr
Schrodinger
18. Pressure in gas discharge tube was kept
10 torr
1 torr
0.1 torr
0.01 torr
19. The number of fundamental particles in an atom of the lightest isotope carbon are
6
12
18
20
20. Angle of deflection was studied by
Hitorff
Stoney
William Crookes
J.Perrin
21. Increase in atomic number is observed during
Alpha emission
Beta emission
Both a & b
Radioactivity
22. Positive rays give flash on
AgNO3 plate
AgCl plate
ZnO
ZnS
23. Free neutron changes into proton with the emission of
Neutrino
Electron
Both a & b
Meson
24. The value of e/m ratio of electron is
6.02 x 1023 C/kg
1.7588 x 1020 C/kg
9.1095 x 10-31 C/kg
1.7588 x 1011 C/kg
25. Charge of electron was measured by
J.J Thomson
Millikan
Rutherford
Perrin
26. Rutherford bombarded ______________ particles in discovery of nucleus
Gamma-rays
Alpha-rays
Beta-rays
X-rays
27. Planks theory says energy is emitted
In continuous manner
Discontinuous manner
Simultaneously
In the form of heat
28. Angular momentum of an electron
n2h/2?
nk2/2?
nh/4?
nh/2?
29. 2nd orbit is _______ away from nucleus of H-atom as compared to 1st orbit is
2-times
3-times
4-times
6 times
30. The maximum number of orbitals present in a subshell that is represented by Azimuthal quantum number = 3 will be
1
3
5
7
31. The correct electronic configuration of Cu is
[Ar]4s1
[Ar]4s2
[Ar]3d104s1
[Ar]3d94s2
32. Pfund series are produced in the spectrum of hydrogen atom
when electrons jump down to 2nd- orbit
when electrons jump down to 3rd- orbit
when electrons jump down to 4th- orbit
when electrons jump down to 5th- orbit
33. Atomic orbits having same evergy are called
Degenerate orbitals
Bonding molecular orbitals
Anti bonding molecular orbitals
Half filled orbitals
34. Sommerfelds modification in Bohrs model is
Orbit is cylindrical
Orbit is elliptical
Orbit is longitudinal
Orbit is asymmetrical
35. When electrons collide with heavy metals than ______ are produced.
Beta-rays
Alpha-rays
X-rays
Gamma-rays
36. Plancks equation is
E = mc2
mvr = nh/2?
E = h?
? = h/mv
37. Atom with higher atomic number produces X-rays of
Shorter wavelength
Larger wavelength
X-ray not produced
All are possible
38. Wavelength of electron was verified by
Moseley
Davisson and Germer
Einstein
Roentgen
39. Space around nucleus where finding probability of electrons is maximum is called
Orbital
Orbit is elliptical
subshell
Electron cloud
40. Quantum number which tells the energy of electron is
n
1
m
s
41. Electronic configuration of K is
[Ar]4s2
[Ar]4s1
[Kr]5s1
[He]2s1
42. ____________ can expel proteons from paraffins
Electron
Positron
Neutron
None of above has such capability
43. Milikan used __________ in his atomizer
Milk
Positron
Neutron
None of above has such capability
44. Milikan used __________ in his atomizer
Milk
Honey
Oil
Water
45. Centrifugal forces are balanced in atom by
Attractive forces
Repulsive force
Electrons
Neutrons
46. Spectrum is produced due to
Different wavelength
Different colours
Different intensities
all have little contribution
47. When 6d orbital is complete the entering electron goes into
7f
7s
7p
7d
48. When electron jump into orbit 1 then series obtained is
Lyman
Paschen
Pfund
Brackett
49. Neutrons moving with an energy of 1.2 MeV are called
Fast neutrons
Slow neutrons
Moderate neutrons
All are possible
50. Splitting of spectral lines when atoms are subjected to strong electric filed is called
Zeeman effect
Stark effect
Photoelectric effect
Compton effect
Submit