Deck 28: Atomic Physics

Question 1

The Lyman series is formed by electron transitions in hydrogen that

A)end on the n = 1 shell.
B)begin on the n = 1 shell.
C)end on the n = 2 shell.
D)begin on the n = 2 shell.
E)are between the n = 1 and n = 3 shells.

Answer 1

A

Question 2

If a proton and an electron have the same de Broglie wavelengths,which one is moving faster?

A)the electron
B)the proton
C)They both have the same speed.

Answer 2

A

Question 3

The Balmer series is formed by electron transitions in hydrogen that

A)end on the n = 1 shell.
B)begin on the n = 1 shell.
C)end on the n = 2 shell.
D)begin on the n = 2 shell.
E)are between the n = 1 and n = 3 shells.

Answer 3

C

Question 4

If the maximum possible accuracy in measuring the velocity of a particle increases,the maximum possible accuracy in measuring its position will

A)increase.
B)decrease.
C)not be affected.

Question 5

Which of the following actions will increase the de Broglie wavelength of a speck of dust? (There could be more than one correct choice.)

A)Increase its mass.
B)Increase its speed.
C)Decrease its mass.
D)Decrease its speed.
E)Decrease its momentum.

Question 6

To which of the following values of n does the longest wavelength in the Balmer series correspond?

A)3
B)5
C)1
D)7
E)∞ (very large)

Question 7

The energy difference between adjacent orbit radii in a hydrogen atom

A)increases with increasing values of n.
B)decreases with increasing values of n.
C)remains constant for all values of n.
D)varies randomly with increasing values of n.

Question 8

A proton and an electron are both accelerated to the same final speed.If λ_p is the de Broglie wavelength of the proton and λ_e is the de Broglie wavelength of the electron,then

A)λ_p > λ_e.
B)λ_p = λ_e.
C)λ_p < λ_e.

Question 9

If the maximum possible accuracy in measuring the lifetime of a particle increases,the maximum possible accuracy in measuring its energy will

A)increase.
B)decrease.
C)not be affected.

Question 10

If the wavelength of a photon in vacuum is the same as the de Broglie wavelength of an electron,which one is traveling faster through space?

A)The electron because it has more mass.
B)The photon because photons always travel through space faster than electrons.
C)They both have the same speed.

Question 11

When an atom changes its energy state from n = 4 to n = 2

A)a photon is emitted.
B)a photon is absorbed.
C)two photons are emitted.
D)two photons are absorbed.
E)None of the given answers are correct.

Question 12

A proton and an electron are both accelerated to the same final kinetic energy.If λ_p is the de Broglie wavelength of the proton and λ_e is the de Broglie wavelength of the electron,then

A)λ_p > λ_e.
B)λ_p = λ_e.
C)λ_p < λ_e.

Question 13

If the maximum possible accuracy in measuring the position of a particle increases,the maximum possible accuracy in measuring its velocity will

A)increase.
B)decrease.
C)not be affected.

Question 14

Hydrogen atoms can emit four spectral lines with visible colors from red to violet.These four visible lines emitted by hydrogen atoms are produced by electrons

A)that start in the n = 2 level.
B)that end up in the n = 2 level.
C)that end up in the n = 3 level.
D)that end up in the ground state.
E)that start in the ground state.

Question 15

To which of the following values of n does the shortest wavelength in the Balmer series correspond?

A)3
B)5
C)7
D)1
E)∞ (very large)

Question 16

The Paschen series is formed by electron transitions that

A)end on the n = 1 shell.
B)begin on the n = 1 shell.
C)end on the n = 2 shell.
D)begin on the n = 3 shell.
E)end on the n = 3 shell.

Question 17

Protons are being accelerated in a particle accelerator.When the energy of the protons is doubled,their de Broglie wavelength will

A)increase by a factor of 4.
B)increase by a factor of 2.
C)decrease by a factor of 2.
D)increase by a factor of
E)decrease by a factor of

Question 18

If the maximum possible accuracy in measuring the energy of a particle increases,the maximum possible accuracy in measuring its lifetime will

A)increase.
B)decrease.
C)not be affected.

Question 19

If a proton and an electron have the same speed,which one has the longer de Broglie wavelength?

A)the electron
B)the proton
C)It is the same for both of them.

Question 20

Protons are being accelerated in a particle accelerator.When the speed of the protons is doubled,their de Broglie wavelength will

A)increase by a factor of 4.
B)increase by a factor of 2.
C)decrease by a factor of 2.
D)increase by a factor of
E)decrease by a factor of

Question 21

Consider ground-state helium having two electrons in orbit.If one of the electrons has quantum numbers (n,ℓl,m₁,m_s)of 1,0,0,-1/2 respectively,the quantum numbers for the other electron will be

A)1, 1, 0, -1/2.
B)1, 0, 0, +1/2.
C)1, 1, 1, +1/2.
D)none of the given answers.

Question 22

According to Pauli's exclusion principle,how many electrons in an atom may have a particular set of quantum numbers?

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

Question 23

According to the quantum mechanical model of the hydrogen atom,if the principal quantum number is n,how many different orbital angular momentum quantum numbers are permitted?

A)n/2
B)n
C)2n
D)3n
E)4n

Question 24

What is the atomic number of a neutral atom that has an electron configuration of 1s² 2s² 2p⁶ 3s² 3p²?

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

Question 25

The magnetic quantum number m₁ can have any integer value ranging from

A)-n to +n.
B)-ℓ to +ℓ.
C)0 to n.
D)0 to ℓ.
E)0 to (n-1)

Question 26

The distance between adjacent orbits in a hydrogen atom

A)increases with increasing values of n.
B)decreases with increasing values of n.
C)remains constant for all values of n.
D)varies randomly with increasing values of n.

Question 27

Which of the following values can be taken by the electron spin quantum number,m_s?

A)±1/2
B)0
C)±1
D)±2
E)±3

Question 28

The principal quantum number n can have any integer value ranging from

A)-∞ to +∞.
B)0 to ∞.
C)1 to ∞.
D)1 to 100.

Question 29

In its ground state,the quantum numbers (n,ℓ,m₁,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.

Question 30

The orbital angular momentum quantum number ℓ can have any integer value ranging from

A)0 to n.
B)0 to (n-1).
C)1 to n.
D)1 to (n+1).
E)-n to n.

Question 31

If n = 5,which one of the following is not an allowed magnetic quantum number m₁?

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

Question 32

The electron spin quantum number can have values of

A)-1/2, -1, 0, +1, +1/2.
B)-1/2, -1, +1, +1/2.
C)-1/2, 0, +1/2.
D)-1/2, +1/2.
E)only +1/2.

Question 33

The orbital angular momentum quantum number can take which of the following values for any given value of the principal quantum number,n?

A)ℓ = 0, 1, 2, . . .
B)ℓ = 0, 1, 2, . . . , n
C)ℓ = 0, 1, 2, . . . , (n - 1)
D)ℓ = 1, 2, 3, 4, . . .
E)ℓ = 1, 2, 3, 4, . . ., (n + 1)

Question 34

The figure shows part of the energy level diagram of a certain atom.The energy spacing between levels 1 and 2 is twice that between 2 and 3.If an electron makes a transition from level 3 to level 2,the radiation of wavelength λ is emitted.What possible radiation wavelengths might be produced by other transitions between the three energy levels?

A)both λ/2 and λ/3
B)only λ/2
C)both 2λ and 3λ
D)only 2λ

Question 35

According to the quantum mechanical model of the hydrogen atom,if the orbital angular momentum quantum number is ℓ,there will be how many permitted magnetic quantum numbers?

A)ℓ/2
B)2ℓ
C)2ℓ + 1
D)2ℓ - 1
E)3ℓ

Question 36

If a hydrogen atom originally in a state with principal quantum number n is excited to state n' = 2n,then

A)its radius and binding energy will double.
B)its radius will quadruple and the binding energy will double.
C)its radius will double and the binding energy will quadruple.
D)its radius will quadruple and the binding energy will be reduced by a factor of four.
E)its radius and binding energy will quadruple.

Question 37

The elements in the periodic table that have completely filled shells or subshells are referred to as

A)noble gases.
B)halogens.
C)alkali metals.
D)transition elements.

Question 38

A hydrogen atom is in the 6h state.What is the principal quantum number.

A)0
B)3
C)5
D)6
E)7

Question 39

Which of the following statements are true for the Bohr model of the atom? (There could be more than one correct choice.)

A)The spacing between all the electron shells is the same.
B)The energy difference between all the electron shells is the same.
C)As we look at higher and higher electron shells, they get closer and closer together, but the difference in energy between them gets greater and greater.
D)As we look at higher and higher electron shells, they get farther and farther apart, but the difference in energy between them gets smaller and smaller.
E)There is no general pattern in the spacing of the shells or their energy differences.

Question 40

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

A)0
B)2
C)3
D)4
E)8

Question 41

An electron is moving with the speed of 1780 m/s.What is its de Broglie wavelength? (m_electron = 9.11 × 10^-31 kg,h = 6.626 × 10^-34 J ∙ s)

A)409 nm
B)302 nm
C)205 nm
D)420 nm
E)502 nm

Question 42

A proton has a speed of 7.2 x m/s.What is the energy of a photon that has the same wavelength as the de Broglie wavelength of this proton? (m_electron = 9.11 × 10^-31 kg,c = 3.00 × 10⁸ m/s,h = 6.626 × 10^-34 J ∙ s)

A)230 keV
B)150 keV
C)300 keV
D)370 keV
E)440 keV

Question 43

What is the de Broglie wavelength of a ball of mass 200 g moving at 30 m/s? (h = 6.626 × 10^-34 J ∙ s)

A)1.1 × 10^-34 m
B)2.2 × 10^-34 m
C)4.5 × 10^-28 m
D)6.7 × 10^-27 m

Question 44

What is the wavelength of the matter wave associated with an electron moving with a speed of 2.5 × 10⁷ m/s? (m_electron = 9.11 × 10^-31 kg,h = 6.626 × 10^-34 J ∙ s)

A)29 pm
B)35 pm
C)47 pm
D)53 pm

Question 45

Atoms in crystals are typically separated by distances of 0.10 nm.What kinetic energy must a nonrelativistic electron have,in electron-volts,in order to have a wavelength of 0.10 nm? (m_electron = 9.11 × 10^-31 kg,1 eV = 1.60 × 10^-19 J,h = 6.626 × 10^-34 J ∙ s)

Question 46

What would be the de Broglie wavelength for 1-g object moving at the earth's escape speed 25,000 mph (about 11 km/s)? (h = 6.626 × 10^-34 J ∙ s)

Question 47

If the de Broglie wavelength of an electron is 2.4 μm,what is the speed of the electron?

A)3.0 × 10² m/s
B)2.5 × 10⁵ m/s
C)1.7 × 10³ m/s
D)8.3 × 10⁶ m/s

Question 48

A person of mass 50 kg has a de Broglie wavelength of 4.4 × 10^-36 m while jogging.How fast is she running? (h = 6.626 × 10^-34 J ∙ s)

A)2.0 m/s
B)3.0 m/s
C)4.0 m/s
D)5.0 m/s

Question 49

If the de Broglie wavelength of an electron is 380 nm,what is the speed of this electron? (m_electron = 9.11 × 10^-31 kg,h = 6.626 × 10^-34 J ∙ s)

A)2.0 km/s
B)3.8 km/s
C)1.9 km/s
D)4.1 km/s
E)5.2 km/s

Question 50

Calculate the kinetic energy,in electron-volts,of a neutron that has a de Broglie wavelength of (m_neutron = 1.675 × 10^-27 kg,1 eV = 1.6 × 10^-19 J,h = 6.626 × 10^-34 J ∙ s)

Question 51

If an electron has the same de Broglie wavelength as the wavelength of a 390-nm photon in vacuum,what is the speed of the electron? (m_electron = 9.11 × 10^-31 kg,c = 3.0 × 10⁸ m/s,h = 6.626 × 10^-34 J ∙ s)

A)1900 m/s
B)2100 m/s
C)1700m/s
D)1500 m/s
E)540 m/s

Question 52

What is the wavelength of the matter wave associated with a 0.50-kg ball moving at 25 m/s? (h = 6.626 × 10^-34 J ∙ s)

A)3.5 × 10^-35 m
B)5.3 × 10^-35 m
C)3.5 × 10^-33 m
D)5.3 × 10^-33 m

Question 53

The electrons in a beam are moving at 18 m/s.(m_electron = 9.11 × 10^-31 kg,h = 6.626 × 10^-34 J ∙ s)
(a)What is its de Broglie wavelength these electrons?
(b)If the electron beam falls normally on a diffraction grating,what would have to be the spacing between slits in the grating to give a first-order maximum at an angle of 30° with the normal to the grating?

Question 54

A crystal diffracts a beam of electrons,like a grating,as they hit it perpendicular to its surface.The crystal spacing is 0.18 nm,and the first maximum scattering occurs at 80° relative to the normal to the surface.(e = 1.60 × 10^-19 C,m_electron = 9.11 × 10^-13 kg,h = 6.626 × 10^-34 J ∙ s)
(a)What is the wavelength of the electrons?
(b)What potential difference accelerated the electrons if they started from rest?

Question 55

If an electron has a wavelength of 0.123 nm,what is its kinetic energy,in electron-volts? This energy is not in the relativistic region.(m_electron = 9.11 × 10^-31 kg,1 eV = 1.60 × 10^-19 J,h = 6.626 × 10^-34 J ∙ s)

A)19.8 eV
B)60.2 eV
C)80.4 eV
D)99.5 eV
E)124 eV

Question 56

If the momentum of an electron is 1.95 × 10^-27 kg ∙ m/s,what is its de Broglie wavelength? (h = 6.626 × 10^-34 J ∙ s)

A)340 nm
B)210 nm
C)170 nm
D)420 nm
E)520 nm

Question 57

After an electron has been accelerated through a potential difference of 0.15 kV,what is its de Broglie wavelength? (e = 1.60 × 10^-19 C,m_electron = 9.11 × 10^-31 kg,h = 6.626 × 10^-34 J ∙ s)

A)0.10 nm
B)1.0 nm
C)1.0 mm
D)1.0 cm

Question 58

Find the de Broglie wavelength of a 1.30-kg missile moving at (h = 6.626 × 10^-34 J ∙ s)

A)1.81 × 10^-35 m
B)2.05 × 10^-35 m
C)2.28 × 10^-35 m
D)2.57 × 10^-35 m

Question 59

How "slow" must a 200-g ball move to have a de Broglie wavelength of 1.0 mm? (h = 6.626 × 10^-34 J ∙ s)

Question 60

A proton that is moving freely has a wavelength of 0.600 pm.(m_proton = 1.67 × 10^-27 kg,e = 1.60 × 10^-19 C,h = 6.626 × 10^-34 J ∙ s)
(a)What is its momentum?
(b)What is its speed?
(c)What potential difference would it have been accelerated through,starting from rest,to reach this speed?

Question 61

The spacing of the atoms of a crystal is 159 pm.A monoenergetic beam of neutrons directed normally at the surface of the crystal undergoes first order diffraction at an angle of 58° from the normal.What is the energy of each of the neutrons? (m_neutron = 1.675 × 10^-27 kg,1 eV = 1.6 × 10^-19 J,h = 6.626 × 10^-34 J ∙ s)

A)0.045 eV
B)0.039 eV
C)0.050 eV
D)0.056 eV
E)0.061 eV

Question 62

What is the value of n in the Balmer series for which the wavelength is 410.2 nm.

A)4
B)5
C)6
D)7
E)9

Question 63

The wavelength of a ruby laser is 694.3 nm.What is the energy difference between the two energy states for the transition that produces this light? (c = 3.00 × 10⁸ m/s,1 eV = 1.60 × 10^-19 J,h = 6.626 × 10^-34 J ∙ s)

A)1.54 eV
B)1.65 eV
C)1.79 eV
D)1.81 eV

Question 64

An electron has the same de Broglie wavelength as the wavelength of a 1.8 eV photon.What is the speed of the electron? (m_electron = 9.11 × 10^-31 kg, c = 3.00 × 10⁸ m/s,1 eV = 1.60 × 10^-19 J)

A)1100 m/s
B)980 m/s
C)910 m/s
D)840 m/s
E)770 m/s

Question 65

Electrons with a speed of 2.1 × 10⁶ m/s are directed towards a 1.0-μm wide slit.An electron detector is placed 1.0 m behind the slit.How wide is the central maximum of the electron diffraction pattern on the detector? (h = 6.626 × 10^-34 J ∙ s,m_electron = 9.11 × 10^-31 kg)

A)690 μm
B)350 μm
C)1000 μm
D)1400 μm

Question 66

A certain crystal has a spacing of 0.442 nm between atoms.A beam of neutrons moving with a speed of 1640 m/s perpendicular to the surface is diffracted as it passes through the crystal.What is the angle from the central maximum to the next interference maximum? (m_neutron = 1.675 × 10^-27 kg,h = 6.626 × 10^-34 J ∙ s)

A)17.0°
B)21.0°
C)33.1°
D)60.0°
E)90.0°

Question 67

What is the longest wavelength in the Paschen series?

A)2.01 nm
B)2.01 μm
C)365 nm
D)1.88 nm
E)1.88 μm

Question 68

What is the shortest wavelength in the Balmer series?

A)328 nm
B)365 nm
C)456 nm
D)656 nm
E)820 nm

Question 69

One of the emission lines described by the original version of Balmer's formula has wavelength What is the value of n in Balmer's formula that gives this emission line?

A)11
B)12
C)13
D)14

Question 70

Electrons are accelerated to a speed of 4.0 × m/s and are then aimed at a double-slit apparatus,where interference fringes are detected.If the electrons were replaced by neutrons,what speed must neutrons have to produce interference fringes with the same fringe spacing as that observed with the electrons? (h = 6.626 × 10^-34 J ∙ s,m_electron = 9.11 × 10^-31 kg,m_neutron = 1.675 × 10^-27 kg)

A)2.2 × 10¹ m/s
B)7.3 × 10⁷ m/s
C)1.7 × 10⁶ m/s
D)9.3 × 10² m/s

Question 71

An electron is accelerated from rest through a potential difference.After acceleration the electron has a wavelength of 880 nm.What is the potential difference responsible for the acceleration of the electron? (h = 6.626 × 10^-34 J ∙ s,m_electron = 9.11 × 10-31 kg,e = 1.6 10^-19 C)

A)1.9 × 10^-6 V
B)1.7 × 10^-6 V
C)2.2 × 10^-6 V
D)2.5 × 10^-6 V

Question 72

What is the longest wavelength in the Lyman Series?

A)45.60 nm
B)91.20 nm
C)121.5 nm
D)240.1 nm
E)365 nm

Question 73

The value of a wavelength in the Balmer series is 372.1 nm.What is the corresponding value of n?

A)6
B)3
C)9
D)10
E)14

Question 74

What is the wavelength in the Balmer series for n = 15?

A)277.1 nm
B)371.1 nm
C)188.6 nm
D)656 nm
E)754.2 nm

Question 75

What value of n corresponds to a wavelength of 91.7 nm in the Lyman series?

A)1
B)3
C)5
D)9
E)13

Question 76

What is the longest wavelength in the Balmer series?

A)240 nm
B)328 nm
C)365 nm
D)656 nm
E)820 nm

Question 77

What is the shortest wavelength in the Paschen series?

A)410.2 nm
B)410.2 μm
C)365 nm
D)820.4 nm
E)820.4 μm

Question 78

What value of n corresponds to a wavelength of 922.7 nm in the Paschen series?

A)3
B)5
C)7
D)9
E)15

Question 79

Electrons emerge from an electron gun with a speed of 2.0 × 10⁶ m/s and then pass through a double-slit apparatus.Interference fringes with spacing of 2.7 mm are detected on a screen far from the double slit.What would the fringe spacing be if the electrons were replaced by neutrons with the same speed? (h = 6.626 × 10^-34 J ∙ s,m_electron = 9.11 × 10^-31 kg,m_neutron = 1.675 × 10^-27 kg)

A)1.5 μm
B)4.9 m
C)0.93 nm
D)1.2 km

Question 80

What is the shortest wavelength of the Lyman series?

A)91.16 nm
B)45.60 nm
C)121.5 nm
D)204.1 nm
E)365 nm