Chapter 38. The work function of metal A is 3.0 eV. Metals B and C have work functions of 4.0 eV and 5.0 eV, respectively. Ultraviolet light shines on.

Post on 22-Dec-2015

271 Views

Category:

Documents

0 Downloads

Preview:

Click to see full reader

Transcript

Chapter 38

The work function of metal A is 3.0 eV. Metals B and C have work functions of 4.0 eV and 5.0 eV, respectively. Ultraviolet light shines on all three metals, creating photoelectrons. Rank in order, from largest to smallest, the stopping voltages for A, B, and C.

1. VA > VB > VC 2. VC > VB > VA 3. VA = VB = VC

The work function of metal A is 3.0 eV. Metals B and C have work functions of 4.0 eV and 5.0 eV, respectively. Ultraviolet light shines on all three metals, creating photoelectrons. Rank in order, from largest to smallest, the stopping voltages for A, B, and C.

1. VA > VB > VC 2. VC > VB > VA 3. VA = VB = VC

The intensity of a beam of light is increased but the light’s frequency is unchanged. Which of the following is true?

1. The photons travel faster.2. Each photon has more energy.3. There are more photons per second. 4. The photons are larger.

The intensity of a beam of light is increased but the light’s frequency is unchanged. Which of the following is true?

1. The photons travel faster.2. Each photon has more energy.3. There are more photons per second. 4. The photons are larger.

What is the quantum number of this particle confined in a box?

1. n = 32. n = 43. n = 54. n = 65. n = 8

What is the quantum number of this particle confined in a box?

1. n = 32. n = 43. n = 54. n = 65. n = 8

A photon with a wavelength of 414 nm has energy Ephoton = 3.0 eV. Do you expect to see a spectral line with = 414 nm in the emission spectrum of the atom represented by this energy-level diagram? If so, what transition or transitions will emit it?

A photon with a wavelength of 414 nm has energy Ephoton = 3.0 eV. Do you expect to see a spectral line with = 414 nm in the emission spectrum of the atom represented by this energy-level diagram? If so, what transition or transitions will emit it?

A photon with a wavelength of 414 nm has energy Ephoton = 3.0 eV. Do you expect to see a spectral line with λ = 414 nm in the absorption spectrum of the atom represented by this energy-level diagram? If so, what transition or transitions will absorb it?

A photon with a wavelength of 414 nm has energy Ephoton = 3.0 eV. Do you expect to see a spectral line with λ = 414 nm in the absorption spectrum of the atom represented by this energy-level diagram? If so, what transition or transitions will absorb it?

What is the quantum number of this hydrogen atom?

1. n = 12. n = 23. n = 34. n = 45. n = 5

What is the quantum number of this hydrogen atom?

1. n = 12. n = 23. n = 34. n = 45. n = 5

Chapter 38Reading Quiz

Who first postulated the idea of light quanta?

1. Planck2. Bohr3. De Broglie4. Einstein5. Heisenberg

Who first postulated the idea of light quanta?

1. Planck2. Bohr3. De Broglie4. Einstein5. Heisenberg

Cite one experiment that confirms the de Broglie hypothesis.

1. Spectrum of blackbody radiation2. X-ray penetration depth3. Electron diffraction4. Optical pumping5. Nuclear magnetic resonance

Cite one experiment that confirms the de Broglie hypothesis.

1. Spectrum of blackbody radiation2. X-ray penetration depth3. Electron diffraction4. Optical pumping5. Nuclear magnetic resonance

What is the name of the diagram used to represent the stationary states of an atom?

1. Atomic-state diagram2. Energy-level diagram3. Standing wave diagram4. Atomic orbital diagram5. Feynman diagram

What is the name of the diagram used to represent the stationary states of an atom?

1. Atomic-state diagram2. Energy-level diagram3. Standing wave diagram4. Atomic orbital diagram5. Feynman diagram

In the photoelectric effect experiment, current flows when the light frequency is

1. less then the threshold frequency.2. equal to the threshold frequency.3. greater then the threshold frequency.4. less than the cathode’s work function.5. equal to the cathode’s work function.

In the photoelectric effect experiment, current flows when the light frequency is

1. less then the threshold frequency.2. equal to the threshold frequency.3. greater then the threshold frequency.4. less than the cathode’s work function.5. equal to the cathode’s work function.

The minimum amount of energy needed to free an electron from a piece of metal is called the

1. Gibb’s free energy.2. quantum energy.3. liberation potential.4. threshold energy.5. work function.

The minimum amount of energy needed to free an electron from a piece of metal is called the

1. Gibb’s free energy.2. quantum energy.3. liberation potential.4. threshold energy.5. work function.

The Bohr model successfully explained the spectrum of

1. hydrogen.2. helium.3. hydrogen and helium.4. all the naturally occurring elements.5. all the elements in the periodic table.

The Bohr model successfully explained the spectrum of

1. hydrogen.2. helium.3. hydrogen and helium.4. all the naturally occurring elements.5. all the elements in the periodic table.

top related