Chapter 8

Modern Atomic Theory

Multiple Choice:

  1. The color patterns observed in soap film are examples of a
  2. line spectrum.
  3. Bohr’s atom.
  4. continuous spectrum.
  5. ultraviolet radiation.

Answer:

  1. The light emitted by an incandescent bulb (a typical tungsten-filament light bulb) is best described as a
  2. line spectrum.
  3. continuous spectrum.
  4. discrete spectrum.
  5. Bohr spectrum.

Answer:

  1. The distance separating adjacent troughs on a wave is called the
  2. frequency.
  3. wavelength.
  4. amplitude.
  5. intensity.

Answer:

  1. The energy of electromagnetic radiation is
  2. proportional to the frequency.
  3. proportional to 1 divided by the wavelength.
  4. inversely proportional to the wavelength.
  5. all of the above.

Answer:

  1. Which region of the electromagnetic spectrum occupies the smallest, most narrow wavelength range?
  2. x-ray region
  3. radio region
  4. infrared region
  5. visible region

Answer:

  1. The frequency of light is inversely proportional to the
  2. Wavelength.
  3. Amplitude.
  4. Speed of light.
  5. Energy.

Answer:

  1. Which one of the following forms of radiation has the shortest wavelength?
  2. x-rays
  3. radio waves
  4. infrared waves
  5. visible waves

Answer:

  1. Which one of the following forms of radiation has the highest frequency?
  2. x-rays
  3. radio waves
  4. infrared waves
  5. visible waves

Answer:

  1. The frequency of light is directly proportional to the
  2. wavelength.
  3. amplitude.
  4. speed of light.
  5. energy.

Answer:

  1. A line spectrum can be used to
  2. identify the chemical substance producing the spectrum.
  3. determine the energy separation between electronic levels.
  4. determine the refractive index of the prism.
  5. Both a and b.

Answer:

  1. Which one of the following produces a discrete spectrum?
  2. stop light
  3. flashlight
  4. the sun
  5. reflection from the moon

Answer:

  1. Which one of the following correctly represents the relationship between the energy and the wavelength of light?
  2. E 
  3. E 
  4. E  1/
  5. E  1/

Answer:

  1. Which one of the following correctly represents the relationship between the energy and the frequency of light?
  2. E 
  3. E 
  4. E  1/
  5. E  1/

Answer:

  1. The energy of light is inversely proportional to the wavelength (). Which one of the following equalities relates the correct proportionality?
  2. E = h
  3. E = hc/
  4. E = /hc
  5. E = 

Answer:

  1. In Bohr’s model of the atom, the orbits that the electron can occupy are said to be
  2. continuous.
  3. quantized.
  4. bonded.
  5. elliptical.

Answer:

  1. A ramp used for wheel-chair access is a good example of a
  2. quantized system.
  3. discrete energy levels.
  4. line spectrum
  5. continuous spectrum.

Answer:

  1. To side-step the failings of Classical mechanics, Bohr proposed that
  2. the electrons are particles.
  3. the electrons are waves.
  4. the electronic energy levels are quantized.
  5. the electrons are excitable.

Answer:

  1. In the ground state, the electron in the hydrogen atom is found
  2. in the n = 0 state.
  3. in the n = 1 state.
  4. in theℓ = 1 state.
  5. at the nucleus.

Answer:

  1. When an electron relaxes back down to the ground state,
  2. it absorbs energy.
  3. it emits a photon with a frequency equal to E/h.
  4. it absorbs a photon with a frequency equal to E/h.
  5. it conserves its energy.

Answer:

  1. Denim jeans appear to be blue in color because
  2. The molecules in the denim fabric absorb blue light.
  3. The molecules in the denim fabric emit all colors except for blue.
  4. The molecules in the denim fabric emit red and green light, absorbing the blue.
  5. The molecules in the denim fabric absorb all visible light and reflect blue light.

Answer:

  1. Artificial turf used as a surface at sporting events appears to be green in color because
  2. The molecules in the turf absorb all visible light and reflect green light.
  3. The molecules in the turf emit all colors except for green.
  4. The molecules in the turf emit red and blue light, absorbing the green.
  5. The molecules in the turf absorb green light.

Answer:

  1. The red color of a rose is due to which one of the following?
  2. The molecules in the flower absorb red light.
  3. The molecules in the flower emit all visible light except for red.
  4. The molecules in the flower absorb all visible light and reflect red light.
  5. The molecules in the flower emit blue and green light, absorbing the red.

Answer:

  1. For an electron to occupy an excited state (n > 1),
  2. the positive charge of the nucleus must “push” it up.
  3. the electron must release energy.
  4. the magnetic component of radiation “attracts” the electron away from the nucleus.
  5. the electron must absorb energy.

Answer:

  1. Based on the properties of an electron, it is classified as
  2. a particle.
  3. a wave.
  4. both a particle and a wave.
  5. neither, really.

Answer:

  1. Although it is still used by scientists today, which one of the following explains why Bohr’s model of the atom is not entirely correct?
  2. Excited states do not exist above the electronic ground state.
  3. Bohr’s model accounts for the emission spectra of heavy atoms, but not hydrogen.
  4. Bohr views the electron solely as a particle, possessing definite mass and velocity.
  5. Bohr views the orbits available to the electrons as unquantized.

Answer:

  1. Wave mechanics, which superseded Bohr’s model, take into account
  2. the proton-electron repulsions.
  3. the probability that electrons exist.
  4. the dual nature (particle/wave) of the electron.
  5. the existence of more than four principal energy levels.

Answer:

  1. For a particular element, a photon of orange light of wavelength of 585 nm resulted when an electron fell from the third energy level to the second energy level. From this information we can determine
  2. the energy of the n = 2 level.
  3. the energy of the n = 3 level.
  4. the difference in energies between n = 2 and n = 3.
  5. the sum of the energies of n = 2 and n = 3.

Answer:

  1. The pictures that are drawn to depict atomic orbitals represent
  2. the 90% probability of finding the electron in this space.
  3. the abstract nature of the atom.
  4. the exact locations of the electrons.
  5. the unique symmetry of the atom.

Answer:

  1. The images of the orbitals (s,p,d) that are in the text represent the
  2. exact location of the electrons.
  3. symmetry of the atom.
  4. electron density.
  5. abstract nature of atoms.

Answer:

  1. Which one of the following orbitals represents a p orbital?

a.

b.

c.

d.

Answer:

  1. How many p orbitals can exist in a single subshell?
  2. 1
  3. 2
  4. 3
  5. not enough information

Answer:

  1. For the n = 2 electronic shell, what is the maximum number of orbitals that can be occupied by electrons?
  2. 1
  3. 2
  4. 3
  5. 4

Answer:

  1. How many orbitals and electrons are in an s shell?
  2. 1 : 4
  3. 1 : 2
  4. 2 : 2
  5. 2 : 1

Answer:

  1. How many d orbitals can exist in a single subshell?
  2. 1
  3. 3
  4. 5
  5. 7

Answer:

  1. Which one of the following correctly depicts the relative energies of the four types of subshells?
  2. p < d < s < f
  3. f < d < p < s
  4. s < p < d < f
  5. d < s < f < p

Answer:

  1. Which one of the following correctly represents the number of nodal planes present in the s, p, d, and f orbitals, respectively?
  2. 0, 1, 2, 3
  3. 1, 3, 5, 7
  4. 0, 2, 4, 6
  5. 1, 2, 3, 4

Answer:

  1. Given the following p orbital,, what is the probability that the electron is found at the point separating the two lobes?
  2. infinite probability
  3. 90% probability
  4. zero probability
  5. 10% probability

Answer:

  1. If there is zero probability of ever finding the electron at the node in a p orbital, then the electron is able to move from one lobe to another because
  2. it is moving very fast.
  3. it is behaving as a wave.
  4. it is behaving as a particle.
  5. it really can only occupy one lobe or the other.

Answer:

  1. For the n = 3 shell, what is the maximum number of orbitals available for electron occupation?
  2. 9
  3. 18
  4. 5
  5. 3

Answer:

  1. For the n = 5 shell, how many electrons are required to completely fill this shell?
  2. 8
  3. 18
  4. 32
  5. 50

Answer:

  1. Given the following four atomic orbitals, 4p, 3s, 4s, 3d, which one of the following correctly represents their relative energies (in increasing order)?
  2. 4p < 3s < 4s < 3d
  3. 3d < 3s < 4s < 4p
  4. 3s < 3d < 4p < 4s
  5. 3s < 4s < 3d < 4p

Answer:

  1. What is the maximum number of electrons that can occupy any given orbital?
  2. 1
  3. 2
  4. 3
  5. 5

Answer:

  1. The principle by which electrons are distributed into available subshells with the lowest energy, is known as
  2. Hund’s principle.
  3. the Pauli exclusion principle.
  4. the Aufbau principle.
  5. Archimedes’ principle.

Answer:

  1. Which one of the following correctly represents the electron configuration for iron?
  2. 1s2 2s2 2p6 3s2 3p6 3d6
  3. [Kr] 5s2 4d6
  4. [Kr] 4s1 3d7
  5. [Ar] 4s2 3d6

Answer:

  1. Which list of chemical species could possess the electron configuration, 1s22s22p6?
  2. Ne, Ar, Kr
  3. F1-, Ne, Na1+
  4. Ne, O2-, Na1+
  5. F, Ne, Na

Answer:

  1. Which element listed below has the electron configuration [Kr]5s2 4d3?
  2. Nb
  3. Zr
  4. V
  5. Ta

Answer:

  1. Which one of the following correctly represents the electron configuration for europium (Eu)?
  2. [Rn] 6s2 4f7
  3. [Xe] 6s2 4f7
  4. [Xe] 6s2 5d1 4f7
  5. [Xe] 5s2 4d1 3f7

Answer:

  1. Which one of the following correctly represents the electron configuration for molybdenum (Mo)?
  2. 1s2 2s2 2p6 3s2 3p6 4s2 3d10 4p6 5s2 4d4
  3. [Ar] 5s1 4d5
  4. [Ar] 5s2 4d4
  5. [Kr] 5s2 4d4

Answer:

  1. Which family in the periodic table has the following general electron configuration, [NG] ns2 np4, where NG represents a noble gas?
  2. Group VIB
  3. Group VIA
  4. Group IVA
  5. Group IIA

Answer:

  1. Which family in the periodic table has the following general electron configuration, [NG] ns2 (n-1)d5, where NG represents a noble gas?
  2. Group VIIB
  3. Group VIIA
  4. Group VB
  5. GroupVA

Answer:

  1. Which two elements on the periodic table have the following general electron configuration, [NG] ns2 (n-2)f10 (n-1)d1, where NG represents a noble gas?
  2. Dy and Cf
  3. La and Ac
  4. Lu and Lr
  5. Ba and Ra

Answer:

  1. When considering the following orbital box diagram, ↑↓, why are arrows pointing in opposite directions?
  2. To illustrate that the electrons are behaving as waves.
  3. To illustrate that the electrons are obeying Hund’s rule.
  4. To illustrate that the electrons have opposite spins.
  5. To reinforce the concept that there are a maximum of two electrons per orbital.

Answer:

  1. Which one of the following orbital diagrams is impossible, according to the Pauli exclusion principle?

1s2s2p

a.()()( )( )( )

b.()()( )( )( )

c.()()()( )( )

d.()()()()()

Answer:

  1. The following orbital diagram violates which principle or rule?

1s2s2p

( )()()( )( )

  1. Aufbau principle
  2. Pauli Exclusion principle
  3. Hund’s rule
  4. Uncertainty principle

Answer:

  1. The following orbital diagram violates which principle or rule?

1s2s2p

( )()()( )( )

  1. Aufbau principle
  2. Pauli Exclusion principle
  3. Hund’s rule
  4. Uncertainty principle

Answer:

  1. Arrange the following elements in order of increasing atomic radius; Al, Si, Ga, and Ge.
  1. Ge < Ga < Si < Al
  2. Al < Si < Ga < Ge
  3. Si < Al < Ge < Ga
  4. Si < Ge < Al < Ga

Answer:

  1. Which one of the following series correctly represents the relative atomic radius amongst the elements? The series are listed from the smallest to the largest radius.
  2. Ca, K, Mg, Na
  3. Ca, K, Sr, Na
  4. Na, K, Ca, Sr
  5. Na, Ca, K, Sr

Answer:

58. Which one of the following series correctly represents the relative atomic radius amongst the chemical substances? The series are listed from the smallest to the largest radius.

  1. S 2-, S, K, K1+
  2. S, S 2-, K, K1+
  3. S, S 2-, K1+, K
  4. S 2-, S, K1+, K

Answer:

59. Which comparison of ionic radius is correct?

  1. K+ > Na+
  2. S2- > Cl-
  3. Na+ > F-
  4. K+ > Cl-

Answer:

60. Which comparison of atomic radius is incorrect?

  1. F > Ne
  2. K > Ca
  3. C > B
  4. Cl > F

Answer:

61. The periodic trend for the ionization energy

  1. is the same as for the atomic radius.
  2. increases from left to right in a period.
  3. is based on the ease of removing protons from the nucleus.
  4. is based on an element’s ability to gain electrons.

Answer:

62. Which one of the following series correctly orders the elements in order of increasing ionization energy?

  1. Ca, K, Mg, Na
  2. P, S, Se, Ar
  3. K, Sr, Rb, Ba
  4. Sb, Te, As, Se

Answer:

63. Which one of the following atoms or ions has the largest ionization energy?

  1. Ba
  2. Li1+
  3. O2-
  4. B

Answer:

64. Which one of the following statements is true?

  1. The ionization energy of chlorine is greater than iodine.
  2. The ionization energy of oxygen is greater than nitrogen.
  3. The atomic radius of chlorine is greater than iodine.
  4. The atomic radius of sodium ion (Na1+) is greater than potassium ion (K1+).

Answer:

65. Sodium does not ordinarily form the Na2+ ion because the second electron removed is from

  1. the outermost (valence) shell.
  2. the s-subshell of the outermost (valence) shell.
  3. a noble gas core.
  4. the next highest principal energy level.

Answer:

Short Answer:

66. (T/F) The frequency of light is proportional to the wavelength of light.

67. (T/F) The distance between the energy levels gets smaller as n increases.

68. (T/F) Bohr suggested that the electrons of an atom can be found at any distance from the nucleus.

69. (T/F) The Pauli exclusion principle states that two electrons in the same orbital must have opposite spins.

70. (T/F) Passing the light emitted by hot gaseous atoms through a prism would create a discrete spectrum.

71. (T/F) The colors that we perceive objects possessing are due to electrons in the object relaxing down to lower energy states and emitting light.

72. (T/F) Electron configurations are arbitrary representations of how the electrons are distributed throughout the atom.

73. (T/F) Since a magnesium atom has more electrons than a sodium atom, the magnesium atom must have a larger radius.

74. (T/F) Electrons possess both wave- and particle-like properties.

75. (T/F) Electrons are found in the atomic orbitals.

76. (T/F) A good visual example of “quantized” energy levels would be a ramp.

1