Question 1

A light emitting diode (L.E.D.)emits photons with an energy of   J.What is the energy per mole of photons emitted?

Accepted Answer

A)    J/mol 
B)    J/mol 
C)    J/mol 
D)    J/mol 
E)    J/mol 
A)    J/mol 
B)    J/mol 
C)    J/mol 
D)    J/mol 
E)    J/mol

Question 2

What is the value of the spin quantum number for an electron in a 4p orbital?

Accepted Answer

A)  4 
B)  1 
C)  either   
Or   
D) 
  
E) 
  
A)  4 
B)  1 
C)  either   
Or   
D) 
  
E)

Question 3

All of the following sets of quantum numbers are allowed EXCEPT

Accepted Answer

A)  n = 6,   = 5,   = 1 
B)  n = 6,   = 3,   = 3 
C)  n = 2,   = 0,   = 0 
D)  n = 5,   = 4,   = 6 
E)  n = 5,   = 4,   = 3 
A)  n = 6,   = 5,   = 1 
B)  n = 6,   = 3,   = 3 
C)  n = 2,   = 0,   = 0 
D)  n = 5,   = 4,   = 6 
E)  n = 5,   = 4,   = 3

Question 4

Which of the following is/are correct postulates of Bohr's theory of the hydrogen atom ?
1)The energy of an electron in an atom is quantized (i.e.only specific energy values are possible).
2)The principal quantum number (n),specifies each unique energy level.
3)An electron transition from a lower energy level to a higher energy level results in an emission of a photon of light.

Accepted Answer

A)  1 only 
B)  2 only 
C)  3 only 
D)  1 and 2 
E)  1,2,and 3 
A)  1 only 
B)  2 only 
C)  3 only 
D)  1 and 2 
E)  1,2,and 3

Question 5

According to Heisenberg's ________ principle,it is impossible to simultaneously measure the exact location and energy of an electron.

Accepted Answer

The answer of According to Heisenberg's ________ principle,it is impossible...

Question 6

Which of the following ranks regions of the electromagnetic spectrum in proper order from highest to lowest frequency.

Accepted Answer

A)  radio > ultraviolet> x-rays > visible > microwaves 
B)  x-rays > ultraviolet > visible > microwaves> radio 
C)  microwaves > x-rays > ultraviolet > visible > radio 
D)  ultraviolet > x-rays > microwaves > visible > radio 
E)  visible > microwaves > radio > ultraviolet > x-rays 
A)  radio > ultraviolet> x-rays > visible > microwaves 
B)  x-rays > ultraviolet > visible > microwaves> radio 
C)  microwaves > x-rays > ultraviolet > visible > radio 
D)  ultraviolet > x-rays > microwaves > visible > radio 
E)  visible > microwaves > radio > ultraviolet > x-rays

Question 7

Which of the following statements is/are CORRECT?
1)FM radio waves have longer wavelengths than visible radiation and AM radio waves have shorter wavelengths than visible radiation.
2)Magnetic resonance imaging (MRI)uses a mixture of x-rays and gamma rays.
3)Exposure to ultraviolet (UV)radiation can lead to sunburns.

Accepted Answer

A)  1 only 
B)  2 only 
C)  3 only 
D)  1 and 2 
E)  1,2,and 3 
A)  1 only 
B)  2 only 
C)  3 only 
D)  1 and 2 
E)  1,2,and 3

Question 8

The difference in energy between adjacent energy levels in an atom _____ as n increases.

Accepted Answer

The answer of The difference in energy between adjacent energy...

Question 9

The electron in a hydrogen atom,originally in level   ,undergoes a transition to a lower level by emitting a photon of wavelength 3745 nm.What is the final level of the electron? (  
  )

Accepted Answer

A)  5 
B)  6 
C)  8 
D)  9 
E)  1 
A)  5 
B)  6 
C)  8 
D)  9 
E)  1

Question 10

If the de Broglie wavelength of an electron is 44 nm,what is its velocity? The mass of an electron is 9.11 $\times$ 10-31 kg.

Accepted Answer

A)  6.0 $\times$ 10-5 m/s 
B)  1.2 $\times$ 103 m/s 
C)  1.7 $\times$ 104 m/s 
D)  3.1 $\times$ 1010 m/s 
E)  4.8 $\times$ 1022 m/s 
A)  6.0 $\times$ 10-5 m/s 
B)  1.2 $\times$ 103 m/s 
C)  1.7 $\times$ 104 m/s 
D)  3.1 $\times$ 1010 m/s 
E)  4.8 $\times$ 1022 m/s

Question 11

The size of an electron orbital is often chosen to be the distance within which 90% of the electron density is found.Why is the orbital radius not chosen to be the distance within which 100% of the electron density is found?

Accepted Answer

The probability of finding an electron d

Question 12

What is the wavelength of a photon that has an energy of   J?

Accepted Answer

A)    nm 
B)    nm 
C)  0.842 nm 
D)    nm 
E)    nm 
A)    nm 
B)    nm 
C)  0.842 nm 
D)    nm 
E)    nm

Question 13

Which of the following statements concerning quantum mechanics is/are true?
1)The behavior of submicroscopic particles can sometimes be described as waves.
2)Quantum mechanics limits us to making statistical statements about the location of an electron in an atom.
3)The uncertainty principle is important only for particles of very small mass,such as the electron.

Accepted Answer

A)  1 only 
B)  2 only 
C)  3 only 
D)  2 and 3 
E)  1,2,and 3 
A)  1 only 
B)  2 only 
C)  3 only 
D)  2 and 3 
E)  1,2,and 3

Question 14

A device emits light at 761.7 nm.What is the frequency of this radiation?

Accepted Answer

A)  3.94 $\times$ 10-4 Hz 
B)  1.15 $\times$ 1027 Hz 
C)  3.94 $\times$ 1014 Hz 
D)  2.61 $\times$ 10-37 Hz 
E)  2.61 $\times$ 10-19 Hz 
A)  3.94 $\times$ 10-4 Hz 
B)  1.15 $\times$ 1027 Hz 
C)  3.94 $\times$ 1014 Hz 
D)  2.61 $\times$ 10-37 Hz 
E)  2.61 $\times$ 10-19 Hz

Question 15

What is the energy per mole of photons of light with a wavelength of 976.9 nm?

Accepted Answer

A)    
B)    
C)    
D)    
E)    
A)    
B)    
C)    
D)    
E)

Question 16

What type of orbital is designated n = 4,   = 2,   = 0?

Accepted Answer

A)  4f 
B)  4d 
C)  4p 
D)  4g 
E)  4s 
A)  4f 
B)  4d 
C)  4p 
D)  4g 
E)  4s

Question 17

For which of the following electron transitions would a hydrogen atom emit a photon of the highest energy?

Accepted Answer

A) 
   
B)  
  
C)  
  
D)  
  
A) 
   
B)  
  
C)  
  
D)

Question 18

If the energy of 1.00 mole of photons is 245 kJ,what is the wavelength of the light?

Accepted Answer

A)  122 nm 
B)  488 nm 
C)  1220 nm 
D)  787 nm 
E)  811 nm 
A)  122 nm 
B)  488 nm 
C)  1220 nm 
D)  787 nm 
E)  811 nm

Question 19

If a cordless phone operates at a frequency of 9.00 $\times$ 108 s-1.What is the wavelength of this radiation?

Accepted Answer

A)  0.333 m 
B)  1.99 $\times$ 10-25 m 
C)  3.33 $\times$ 10-9 m 
D)  3.71 $\times$ 10-18 m 
E)  2.70 $\times$ 1017 m 
A)  0.333 m 
B)  1.99 $\times$ 10-25 m 
C)  3.33 $\times$ 10-9 m 
D)  3.71 $\times$ 10-18 m 
E)  2.70 $\times$ 1017 m

Question 20

Which of the following colors of visible light has the highest frequency?

Accepted Answer

A)  green 
B)  orange 
C)  red 
D)  yellow 
E)  blue 
A)  green 
B)  orange 
C)  red 
D)  yellow 
E)  blue

Exam 7: The Structure of Atoms

A light emitting diode (L.E.D.)emits photons with an energy of J.What is the energy per mole of photons emitted?

What is the value of the spin quantum number for an electron in a 4p orbital?

All of the following sets of quantum numbers are allowed EXCEPT

According to Heisenberg's ________ principle,it is impossible to simultaneously measure the exact location and energy of an electron.

Which of the following ranks regions of the electromagnetic spectrum in proper order from highest to lowest frequency.

The difference in energy between adjacent energy levels in an atom _____ as n increases.

The electron in a hydrogen atom,originally in level ,undergoes a transition to a lower level by emitting a photon of wavelength 3745 nm.What is the final level of the electron? ( )

If the de Broglie wavelength of an electron is 44 nm,what is its velocity? The mass of an electron is 9.11 ×\times× 10-31 kg.

The size of an electron orbital is often chosen to be the distance within which 90% of the electron density is found.Why is the orbital radius not chosen to be the distance within which 100% of the electron density is found?

What is the wavelength of a photon that has an energy of J?

A device emits light at 761.7 nm.What is the frequency of this radiation?

What is the energy per mole of photons of light with a wavelength of 976.9 nm?

What type of orbital is designated n = 4, = 2, = 0?

For which of the following electron transitions would a hydrogen atom emit a photon of the highest energy?

If the energy of 1.00 mole of photons is 245 kJ,what is the wavelength of the light?

If a cordless phone operates at a frequency of 9.00 ×\times× 108 s-1.What is the wavelength of this radiation?

Which of the following colors of visible light has the highest frequency?

Basic Concepts of Chemistry

Mathlets Review: The Tools of Quantitative Chemistry

Atoms, molecules, and Ions

Chemical Reactions

Stoichiometry: Quantitative Information About Chemical Reactions

Principles of Chemical Reactivity: Energy and Chemical Reactions

The Structure of Atoms and Periodic Trends

Bonding and Molecular Structure

Bonding and Molecular Structure: Orbital Hybridization and Molecular Orbitals

Gases and Their Properties

Intermolecular Forces and Liquids

The Chemistry of Solids

Solutions and Their Behavior

Chemical Kinetics: the Rates of Chemical Reactions

Principles of Reactivity: Chemical Equilibria

The Chemistry of Acids and Bases

Principles of Reactivity: Other Aspects of Aqueous Equilibria

Entropy and Free Energy

Principles of Reactivity: Electron Transfer Reactions

Environmental Chemistry Earths Environment,energy,and Sustainability

The Chemistry of the Main Group Elements

The Chemistry of the Transition Elements

Carbon: Not Just Another Element

Biochemistry

Nuclear Chemistry

Filters

If the de Broglie wavelength of an electron is 44 nm,what is its velocity? The mass of an electron is 9.11 $\times$ 10^-31 kg.

If a cordless phone operates at a frequency of 9.00 $\times$ 10⁸ s^-1.What is the wavelength of this radiation?