Deck 41: Atomic Structure

Question 1

How fast must a hydrogen atom be traveling for its kinetic energy to be just enough to excite the ground-state atom to its first excited state in a collision? (1 eV = 1.60 × 10^-19 J,

A) 44.2 km/s
B) 21.7 km/s
C) 66.5 km/s
D) 113 km/s
E) 51.0 km/s

Answer 1

44.2 km/s

Question 2

Which of the following electron transitions is forbidden?

A) 3s → 2p
B) 3d → 2p
C) 3d → 1s
D) 4p → 1s

Answer 2

3d → 1s

Question 3

An electron in a hydrogen atom is in the n = 7 shell.How many possible values of the orbital quantum number l could it have?

A) 6
B) 7
C) 15
D) 33
E) 98

Answer 3

7

Question 4

If two electrons in an atom have the same energy,then they must have the same four quantum numbers.

Question 5

What is the energy of an incident photon that is just enough to excite a hydrogen atom from its ground state to its n = 4 state?

A) 12.75 eV
B) 10.20 eV
C) 3.40 eV
D) 0.85 eV

Question 6

The binding energy of the hydrogen atom in its ground state is -13.6 eV.What is the energy when it is in the n = 5 state?

A) 2.72 eV
B) -2.72 eV
C) 0.544 eV
D) -0.544 eV
E) -68 eV

Question 7

An electron in a hydrogen atom has orbital quantum number l = 7.How many possible values of the magnetic quantum number m_l could it have?

A) 6
B) 7
C) 15
D) 33
E) 98

Question 8

If the orbital quantum number is l = 4,which one of the following is a possible value for the principal quantum number n?

A) 1
B) 2
C) 3
D) 4
E) 8

Question 9

An electron initially in a 4p state decays to a lower energy state.Which energy state is forbidden?

A) 3d
B) 2p
C) 2s
D) 1s

Question 10

In the ground state,the quantum numbers (n,l,m_l,m_s)for hydrogen are,respectively

A) 1, 1, 1, 1
B) 1, 0, 0, 0
C) 1, 0, 0, ± 1/2
D) 1, 1, 1, ± 1/2
E) 1, 1, 0, ± 1/2

Question 11

Two entangled fermions each have equal probabilities of being in one of two states (state 1 or state 2).The fermions are separated so that no forces act between them.One of the fermions is then studied and found to be in state 1.What is the probability that,when studied,the second particle will also be found in state 1?

A) 0%
B) 33%
C) 50%
D) 67%
E) 100%

Question 12

An electron in a hydrogen atom has principal quantum number n = 4.How many possible values of the orbital quantum number l could it have?

A) 8
B) 9
C) 3
D) 4
E) 10

Question 13

If two electrons in the same atom have the same four quantum numbers,then they must have the same energy.

A) True
B) False
C) They cannot both have the same four quantum numbers.

Question 14

If an electron has spin quantum number m_s = -1/2 what is the possible value for the orbital quantum number l of the electron?

A) 0
B) 1
C) 2
D) 11
E) All of the above numbers are possible.

Question 15

For each value of the principal quantum number n,what are the possible values of the electron spin quantum number m_s? (There may be more than one correct choice.)

A) 0
B) +1/2
C) -1/2
D) +3/2
E) -3/2

Question 16

An electron in a hydrogen atom has orbital quantum number l = 4.How many possible values of the magnetic quantum number m_l could it have?

A) 4
B) 10
C) 5
D) 9
E) 3

Question 17

What element has a K_α line with wavelength 1.46 × 10^-11 m?

A) Zirconium
B) Niobium
C) Uranium
D) Protactinium

Question 18

Consider the four quantum numbers of an electron in an atom,n,l,m_l,and m_s.The energy of an electron in an isolated atom depends on

A) n only.
B) n and l only.
C) n, l, and m_l only.
D) l, m_l, and m_s only.
E) all four quantum numbers.

Question 19

Electrons in the presence of a magnetic field transition from 4p energy states to 3d states.How many different spectral lines could be observed from these transitions?

A) one
B) two
C) three
D) five

Question 20

If the principal quantum number of an electron is n = 5,which one of the following is NOT an allowed magnetic quantum number m_l for the electron?

A) 0
B) 2
C) 3
D) 4
E) 5

Question 21

An atom has completely filled inner shells and a single valence electron in an excited p state.The filled inner shells have an orbital momentum equal to zero.A magnetic field is applied,defining the z-axis along the field.Which of the following sets of angles are possible angles between the magnetic field and the orbital angular momentum?

A) 45°
B) 90°
C) 45°, 90°
D) 45°, 135°
E) 45°, 90°, 135°

Question 22

The magnitude of the orbital angular momentum L of an electron in a certain atom is equal to 3.464ħ.Which of the following angles could NOT be the angle between the orbital angular momentum vector of the electron and an arbitrary z-direction?

A) 107°
B) 90.0°
C) 73.2°
D) 54.7°
E) 0.00°

Question 23

The only VALID electron state and shell designation among the following is

A) 1p, K.
B) 2s, K.
C) 1s, L.
D) 2p, L.
E) 3f, M.

Question 24

What is the greatest magnitude of the orbital angular momentum L for an electron in a state with principal quantum number n=5?

A) 4.47
B) 4.90
C) 5
D) 5.48

Question 25

What is the electron configuration for ground state Li,which has 3 electrons?

A) 1s³
B) 1s¹2s²
C) 1s²2s¹
D) 1s²1p¹
E) 1s¹1p²

Question 26

A neutral atom has an electron configuration of 1s²2s²2p⁶3s²3p².How many protons does it have in its nucleus?

A) 5
B) 11
C) 14
D) 20
E) 26

Question 27

Consider the n = 9 shell.
(a)What is the largest value of the orbital quantum number,l,in this shell?
(b)How many electrons can be placed in this shell?

Question 28

What is the correct electronic configuration for ground state carbon,which has 6 electrons?

A) 1s²2s²2p²
B) 1s¹2p¹
C) 1s¹2s²2p¹
D) 1s¹2s¹2p¹
E) 1s²2s²2p⁴

Question 29

The only INVALID electron state and shell designation among the following is

A) 1s, K.
B) 2s, L.
C) 2d, L.
D) 3s, M.
E) 3d, M.

Question 30

What is the minimum speed needed by a ground-state hydrogen atom for its kinetic energy to be enough to ionize the atom in a collision? (1 eV = 1.60 × 10^-19 J, m_H≈ m_proton =1.67 x 10^-27 kg)

A) 44.2 km/s
B) 21.7 km/s
C) 66.5 km/s
D) 113 km/s
E) 51.0 km/s

Question 31

What is the greatest total angular momentum J for an electron in the n = 2 shell?

A) 1.9
B) 2.5
C) 0.50
D) 3.5
E) 1.5

Question 32

How many electrons can be found with principal quantum number in a suitably heavy atom?

A) 18
B) 6
C) 20
D) 9

Question 33

The magnitude of the orbital angular momentum L of an electron in a certain atom is equal to 3.464ħ.What is the orbital quantum number l of the electron?

A) 1
B) 2
C) 3
D) 4
E) 5

Question 34

The normalized wave function for a hydrogen atom in the 1s state is given by where α₀ is the Bohr radius,which is equal to 5.29 × 10^-11 m.What is the probability of finding the electron at a distance greater than 7.8 α₀ from the proton?

A) 2.3 × 10^-5
B) 1.2 × 10^-5
C) 1.7 × 10^-5
D) 4.6 × 10^-5
E) 3.5 × 10^-5

Question 35

How many electrons does it take to fill the d subshell?

A) 10
B) 6
C) 14
D) 4
E) 8

Question 36

How many possible sets of quantum numbers (electron states)are there in the 5f subshell?

A) 2
B) 6
C) 8
D) 10
E) 14

Question 37

An atom with 5 electrons is in its ground state.How many electrons are in its outermost shell?

Question 38

The magnitude of the orbital angular momentum L of an electron in a certain atom is equal to 3.464ħ.Which one of the following numbers could be the principal quantum number n of the electron?

A) 0
B) 1
C) 2
D) 3
E) 4

Question 39

The correct ground state electron configuration of boron,which has 5 electrons,is

A) 1s²2s²2p.
B) 1s²2s²2p³.
C) 1s²1p²2s.
D) 1s²2p²3s.
E) 1s²2p³.

Question 40

An atom has completely filled inner shells and a single valence electron in an excited p state.The filled inner shells have an orbital momentum equal to zero.What is the magnitude of the orbital angular momentum L of the atom?

A) 1.0ħ
B) 1.2ħ
C) 1.4ħ
D) 1.7ħ
E) 2.0ħ

Question 41

What is the wavelength of the K_α line for Mercury?

A) 1.94 × 10^-11 m
B) 5.38 × 10^-12 m
C) 1.85 × 10^-11 m
D) 3.02 × 10^-12 m

Question 42

Doubly-ionized lithium is a hydrogen-like ion,in which the nucleus with charge 3e is orbited by a single electron.What wavelength light would be emitted from Li⁺⁺ as the electron dropped from the n = 4 to the n = 3 orbit?

A) 16.9 µm
B) 1.88 µm
C) 470 nm
D) 208 nm

Question 43

An atom in a state with its orbital quantum number l = 1 decays to its ground state (with l = 0).A photon of wavelength 630.000 nm is emitted in the process.When the same process takes place in the presence of an intense magnetic field,the following change in the spectrum is observed.With the magnetic field present,one of the emitted lines observed now has a wavelength of 630.030 nm.Which of the following wavelengths would you expect to be also present?

A) 629.970 nm
B) 630.060 nm
C) 630.090 nm
D) 630.120 nm
E) 629.910 nm

Question 44

A three-dimensional potential well has potential U₀ = 0 in the region ,and and infinite potential otherwise.The ground state energy of a particle in the well is E₀.What is the energy of the first excited state,and what is the degeneracy of that state?

A) 2E₀, single degeneracy
B) 2E₀, triple degeneracy
C) 3E₀, single degeneracy
D) 6E₀, single degeneracy
E) 6E₀, triple degeneracy

Question 45

Model a hydrogen atom as a three-dimensional potential well with U₀ = 0 in the region ,and 0 < z < L,and infinite otherwise,with L = 1.0 × 10^-10 m.Which of the following is NOT one of the lowest three energy levels of an electron in this model?

A) 113 eV
B) 226 eV
C) 283 eV
D) 339 eV

Question 46

The energy of an electron in the p-level of an atom is changed in the presence of a magnetic field of magnitude 4.6 T.What is the difference between the largest and smallest possible energies? (Bohr magneton = μ_B = 9.27 × 10^-24 J/T)

Question 47

A three-dimensional potential well has potential U₀ = 0 in the region ,and and infinite potential otherwise.The ground state energy of a particle in the well is E₀.What is the energy of the first excited state,and what is the degeneracy of that state?

A) 2E₀, single degeneracy
B) (4/3)E₀, single degeneracy
C) 2E₀, double degeneracy
D) (7/3)E₀, double degeneracy
E) 3E₀, triple degeneracy

Question 48

An alkali metal atom is in the ground state.The orbital angular momentum equals zero and the spin angular momentum is entirely due to the single valence electron.A magnetic field is applied that splits the ground state energy level into two levels,65 μeV apart.A photon,absorbed by the atom,induces a transition between the two levels.What is the wavelength of the photon? (c = 3.00 × 10⁸ m/s,h = 6.626 × 10^-34 J • s,Bohr magneton = μ_B = ,

A) 19 mm
B) 25 mm
C) 31 mm
D) 38 mm
E) 41 mm

Question 49

What is the correct electronic configuration for the ground state sodium atom,which has 11 electrons?

A) 1s¹2s²3p⁶2s²
B) 1s²2s¹3p⁶2s²
C) 1s¹2s²2p⁶
D) 1s²2s²2p⁶3s²
E) 1s²2s²2p⁶3s¹

Question 50

A muonic hydrogen atom is a proton orbited by a muon (a particle with the same charge as an electron and 207 times its mass)in which the mass of the muon is significant relative to the mass of the proton.What would be the radius of the smallest muon orbit in a muonic hydrogen atom?

A) 1.03 × 10^-8 m
B) 1.10 × 10^-8 m
C) 2.56 × 10^-13 m
D) 2.84 × 10^-13 m
E) 5.29 × 10^-11 m

Question 51

An s state (l = 0)energy level is split into two levels by an applied magnetic field.A photon of microwave radiation having frequency 60 GHz induces a transition between the two levels.What is the magnitude of the applied magnetic field? (h = 6.626 × 10^-34 J • s,

A) 2.1 T
B) 0.34 T
C) 1.2 T
D) 2.8 T
E) 13 T

Question 52

What is the radius of the smallest electron orbit in a singly-ionized helium atom?

A) 1.32 × 10^-11 m
B) 2.65 × 10^-11 m
C) 5.29 × 10^-11 m
D) 1.06 × 10^-10 m

Question 53

An alkali metal atom is in the ground state.The orbital angular momentum equals zero and the spin angular momentum is entirely due to the single valence electron.A magnetic field is applied that splits the ground state energy level into two levels,27 μeV apart.What is the strength of the applied magnetic field? (h = 6.626 × 10^-34 J ∙ s,Bohr magneton = μ_B = ,1 eV = 1.60 × 10^-19 J)

A) 0.23 T
B) 0.18 T
C) 0.29 T
D) 0.34 T
E) 0.40 T