Atomic and Molecular Physics
PHYS455+PHIS455
Mid-Term-2
First Semester (1436-1437)
College of Sciences -Al Zulfi
Duration: 10:00 – 11:00
Date: 18/2/1437
The student's name:
Physics Program
Number of pages: 4 with Cover
Section Group: 1069 + 1108
University ID:
Examination Guidelines
1-
Type your name and university identification number clearly in the space provided.
2-
Use blue or black pen in answer and pencil in drawing.
3-
Books or notes, papers and publications are not allowed into the examination room.
4-
Students are not allowed to get out from the examination room before passing 30
minutes from the beginning of test starting.
Learning Outcomes
The Knowledge Skills
a1
a2
Interpersonal skills and
taking responsibility
Cognitive skills
a3
b1
x
b2
b3
x
c1
x
c2
Communication,
information technology
and numerical skills
d1
d2
d3
x
Grades
Faculty member
…………………………….
Review Committee
Name
Signature
Final grade...…../….......
Corrector 1
/…………….
/…………….
Corrector 2
/…………….
/…………….
/…………….
/…………….
/…………….
/…………….
/…………….
/…………….
/…………….
/…………….
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Learning
outcome
Question
a3
1(a),2
b2
d1
………………..
1(b),
3(b)
3 (a)
College of Sciences -Al Zulfi
Atomic and Molecular Physics
PHYS455+PHIS455
Mid-Term-2
First Semester (1436-1437)
Physics Program
[h=6.625x10-34J.s, c=3x108 m/s, o=8.85x10-12 C2/N. M2 , me=9.11x10-31 kg, e=1.6x10-19 C , R=1.097x107 m-1 ]
Question one:
a) Explain Bohr Magneton, and then calculate their magnitude?
(5 marks)
b) Estimate the energy of the characteristic x-ray emitted from a Tungsten target when
an electron drops from an L shell (n=2) to a vacancy in the K shell (n=1), Z=74 ?
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College of Sciences -Al Zulfi
Atomic and Molecular Physics
PHYS455+PHIS455
Mid-Term-2
First Semester (1436-1437)
Question two:
1)
2)
3)
4)
5)
Physics Program
(5 marks)
Planck’s constant has the same units as:
a) angular momentum
c) the Hamiltonian
b) quantum number
d) de Broglie wavelength
Which of the following is known as the Schrodinger equation
a) E = hν
c) λ = h/p
b) Hˆ ψ = Eψ
d) E = mc2
A hydrogen atom radiates a photon as it falls from a 2p level to the 1s level. The wavelength of the
emitted radiation equals
a) 22.8 nm
c) 91.2 nm
b) 364.7 nm
d) 121.6 nm
The orbital degeneracy of hydrogen atom energy levels equals
a) n-1
c) n
b) n+1
d) 2n+1
According Bohr model For the hydrogen atom, which of the following orbitals has the lowest energy
a) 4s
c) 4p
b) 4d
d) They all have the same energy
6) Which of the following statements about the hydrogen atom ground state is INCORRECT
7)
a) It is described by the quantum numbers n =1, l = 0, m = 0 c) The wavefunction is spherically symmetrical
b) The electron’s angular momentum equals h
d) The wavefunction decreases exponentially as a function of r
The expectation value of 1/r in the ground state of the hydrogen atom equals
a) a0
b) 1/a0
c) (3/2)a0
d) h/mc
8)
The ionization energy for hydrogen atom is 13.6 eV. The ionization energy for the ground state of Li++
is approximately
a) 13.6 eV
c) 27.2 eV
b) 54.4 eV
d) 122.4 eV
9) The magnetic quantum number of an orbital defines:
a) The energy level of the orbital
c) The shape of the orbital
b) The spatial orientation of the orbital
d) The spin of the electrons in the orbital
10)
The electron configuration for gallium (31Ga)is:
a) [Ar]4s24d104p1
c) [Ar]4s23d103p1
b) [Ar]4s23d104p1
d) [Ar]5s23d104p1
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College of Sciences -Al Zulfi
Atomic and Molecular Physics
PHYS455+PHIS455
Mid-Term-2
First Semester (1436-1437)
Physics Program
Question three:
(5marks)
a) State, with reasons, whether any of the following transitions are allowed or forbidden
for electric dipole transitions:
Transition
2
D5/2 → 2P1/2
2
P1/2 → 2S1/2
3
P1 → 1S0
3
D3 → 3D2
2
G7/2 → 2F3/2
Description the state
Reason
a) A diatomic molecule 12C18O which the vibration frequency when the molecule
decay from v=1 to v=0 is 6.42x1013 Hz, find :
1) The elastic constant (k)
2) The maximum amplitude at excited state v=3
3) The wavelength of the emitted photon
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