quantum physics
DESCRIPTION
Quantum Physics. What makes one atom different from another?. The amazing colors produced in fireworks are a result of the different types of atoms that are used. The colors depend on the chemical characteristics of the elements used to make them. - PowerPoint PPT PresentationTRANSCRIPT
Quantum Physics
What makes one atom different from another
The amazing colors produced in fireworks are a result of the different types of atoms that are used
The colors depend on the chemical characteristics of the elements used to make them
What makes one atom different from another
The amazing colors produced in fireworks are a result of the different types of atoms that are used
The colors depend on the chemical characteristics of the elements used to make them
Atomic Spectra
bull There are discrete energy levels for each electron in each atom (quantum mechanics)
bull Absorption of energy results in a transitions to a higher energy level
bull A transition back to a lower level produces a photon of light
bull The frequency of the emitted photon is determined by the difference in the energy levels
Ephoton = hf = E2 ndash E1
bull Each frequency is a different color
Atomic Spectra
bull Since the electrons levels are unique for each element each element produces a unique spectra of colors when supplied energy
Spectra for Neon
Atomic Spectra
bull each element produces a unique spectra of colors viewed through a diffraction grating
Spectra for Neon
The incandescence from the elements occurs when solid particles are heated in the flame to extremely high temperatures This releases excess energy in the form of light
The higher the temperature the shorter the wavelength at which light is emitted and the nearer it tends toward the blue end of the colored spectrum
This is why blue colored fireworks are so hard to synthesize as they only occur at very high temperatures
Metal Color
Strontium Red
Copper Blue
Barium Green
Sodium YellowOrange
Calcium Orange
Gold Iron
The Hydrogen AtomONE
electron
The frequency of the emitted photon is determined by the difference in the energy levelsEphoton = hf = E2 ndash E1
Now you try onehellipbull Get out your calculatorsbull The energized electron in Hydrogen makes a transition from n
= 3 with an energy of -15 eV down to its ground state where its energy is -136 eV
What is the frequency of the emitted photonbull Ephoton = E2 ndash E1 and Ephoton = hfbull Ephoton = -15 eV ndash (-136 eV) = 121 eVbull Ephoton = 121 eV = hf (h = 414 x 10-15 eVs )bull f = 121 eV divide 414 x 10-15 eVs = bull Frequency f = 292 x 1015 Hzbull Is this visible light Use c = lf to find the wavelengthbull wavelength l = 102 x 10-7 = 102 nmbull This is NOT visible light- it is UV
Hydrogen EmissionThe energy of the electron is given by
E =
1Find the Energy of the Hydrogen electron from n = 1 to n = 72 Find the Energy of each photon emitted (Ephoton = DE) for these
transitions4 to 1 5 to 2 6 to 3 7 to 43 to 1 4 to 2 5 to 3 6 to 42 to 1 3 to 2 4 to 3 5 to 43 Find the wavelength for each of those photons and determine
what type of electromagnetic wave they are
2neV613
Light behaves like a wave AND like a particle
The first clear demonstration of the particle-like behavior of light was in
The Photoelectric Effect
Albert Einstein won the Nobel Prize in Physics for his explanation of the Photoelectric Effect
Electromagnetic waves striking a metal surface can liberate electrons from its surface
The photons must have enough energy (high enough frequency) for this effect to occur
The energy of the ldquophotoelectronsrdquo liberated from the surface depends on the frequency of the photon
Increasing the intensity (brightness) of the light increases the number of photoelectrons emitted but not the energy of each electron
The Photoelectric
Effect
When will Photoelectrons be produced
Now you try someIf the threshold wavelength for a particular metal is 320 nm
what is the metalrsquos work function
First find the threshold frequency using c = lf Threshold frequency fo = 938 x 1014 Hz
Now find the work-function hfo = Wo
Wo = 388 eV
What if a 450 nm light hit a surface with a work function of 236 eV What will be the kinetic energy of the photoelectron
First find the frequency of the 450 nm lightf = 667 x 1014 HzNow using conservation of energyhf = Wo + Kinetic energySo K = hf ndash WoK = 040 eV
- Quantum Physics
- Slide 2
- What makes one atom different from another
- What makes one atom different from another (2)
- Atomic Spectra
- Atomic Spectra (2)
- Atomic Spectra (3)
- Slide 8
- Slide 9
- The Hydrogen Atom ONE electron
- Now you try onehellip
- Hydrogen Emission
- Slide 13
- Light behaves like a wave AND like a particle
- Slide 15
- Slide 16
- Slide 17
- Now you try some
- Slide 19
- Slide 20
-
What makes one atom different from another
The amazing colors produced in fireworks are a result of the different types of atoms that are used
The colors depend on the chemical characteristics of the elements used to make them
What makes one atom different from another
The amazing colors produced in fireworks are a result of the different types of atoms that are used
The colors depend on the chemical characteristics of the elements used to make them
Atomic Spectra
bull There are discrete energy levels for each electron in each atom (quantum mechanics)
bull Absorption of energy results in a transitions to a higher energy level
bull A transition back to a lower level produces a photon of light
bull The frequency of the emitted photon is determined by the difference in the energy levels
Ephoton = hf = E2 ndash E1
bull Each frequency is a different color
Atomic Spectra
bull Since the electrons levels are unique for each element each element produces a unique spectra of colors when supplied energy
Spectra for Neon
Atomic Spectra
bull each element produces a unique spectra of colors viewed through a diffraction grating
Spectra for Neon
The incandescence from the elements occurs when solid particles are heated in the flame to extremely high temperatures This releases excess energy in the form of light
The higher the temperature the shorter the wavelength at which light is emitted and the nearer it tends toward the blue end of the colored spectrum
This is why blue colored fireworks are so hard to synthesize as they only occur at very high temperatures
Metal Color
Strontium Red
Copper Blue
Barium Green
Sodium YellowOrange
Calcium Orange
Gold Iron
The Hydrogen AtomONE
electron
The frequency of the emitted photon is determined by the difference in the energy levelsEphoton = hf = E2 ndash E1
Now you try onehellipbull Get out your calculatorsbull The energized electron in Hydrogen makes a transition from n
= 3 with an energy of -15 eV down to its ground state where its energy is -136 eV
What is the frequency of the emitted photonbull Ephoton = E2 ndash E1 and Ephoton = hfbull Ephoton = -15 eV ndash (-136 eV) = 121 eVbull Ephoton = 121 eV = hf (h = 414 x 10-15 eVs )bull f = 121 eV divide 414 x 10-15 eVs = bull Frequency f = 292 x 1015 Hzbull Is this visible light Use c = lf to find the wavelengthbull wavelength l = 102 x 10-7 = 102 nmbull This is NOT visible light- it is UV
Hydrogen EmissionThe energy of the electron is given by
E =
1Find the Energy of the Hydrogen electron from n = 1 to n = 72 Find the Energy of each photon emitted (Ephoton = DE) for these
transitions4 to 1 5 to 2 6 to 3 7 to 43 to 1 4 to 2 5 to 3 6 to 42 to 1 3 to 2 4 to 3 5 to 43 Find the wavelength for each of those photons and determine
what type of electromagnetic wave they are
2neV613
Light behaves like a wave AND like a particle
The first clear demonstration of the particle-like behavior of light was in
The Photoelectric Effect
Albert Einstein won the Nobel Prize in Physics for his explanation of the Photoelectric Effect
Electromagnetic waves striking a metal surface can liberate electrons from its surface
The photons must have enough energy (high enough frequency) for this effect to occur
The energy of the ldquophotoelectronsrdquo liberated from the surface depends on the frequency of the photon
Increasing the intensity (brightness) of the light increases the number of photoelectrons emitted but not the energy of each electron
The Photoelectric
Effect
When will Photoelectrons be produced
Now you try someIf the threshold wavelength for a particular metal is 320 nm
what is the metalrsquos work function
First find the threshold frequency using c = lf Threshold frequency fo = 938 x 1014 Hz
Now find the work-function hfo = Wo
Wo = 388 eV
What if a 450 nm light hit a surface with a work function of 236 eV What will be the kinetic energy of the photoelectron
First find the frequency of the 450 nm lightf = 667 x 1014 HzNow using conservation of energyhf = Wo + Kinetic energySo K = hf ndash WoK = 040 eV
- Quantum Physics
- Slide 2
- What makes one atom different from another
- What makes one atom different from another (2)
- Atomic Spectra
- Atomic Spectra (2)
- Atomic Spectra (3)
- Slide 8
- Slide 9
- The Hydrogen Atom ONE electron
- Now you try onehellip
- Hydrogen Emission
- Slide 13
- Light behaves like a wave AND like a particle
- Slide 15
- Slide 16
- Slide 17
- Now you try some
- Slide 19
- Slide 20
-
What makes one atom different from another
The amazing colors produced in fireworks are a result of the different types of atoms that are used
The colors depend on the chemical characteristics of the elements used to make them
Atomic Spectra
bull There are discrete energy levels for each electron in each atom (quantum mechanics)
bull Absorption of energy results in a transitions to a higher energy level
bull A transition back to a lower level produces a photon of light
bull The frequency of the emitted photon is determined by the difference in the energy levels
Ephoton = hf = E2 ndash E1
bull Each frequency is a different color
Atomic Spectra
bull Since the electrons levels are unique for each element each element produces a unique spectra of colors when supplied energy
Spectra for Neon
Atomic Spectra
bull each element produces a unique spectra of colors viewed through a diffraction grating
Spectra for Neon
The incandescence from the elements occurs when solid particles are heated in the flame to extremely high temperatures This releases excess energy in the form of light
The higher the temperature the shorter the wavelength at which light is emitted and the nearer it tends toward the blue end of the colored spectrum
This is why blue colored fireworks are so hard to synthesize as they only occur at very high temperatures
Metal Color
Strontium Red
Copper Blue
Barium Green
Sodium YellowOrange
Calcium Orange
Gold Iron
The Hydrogen AtomONE
electron
The frequency of the emitted photon is determined by the difference in the energy levelsEphoton = hf = E2 ndash E1
Now you try onehellipbull Get out your calculatorsbull The energized electron in Hydrogen makes a transition from n
= 3 with an energy of -15 eV down to its ground state where its energy is -136 eV
What is the frequency of the emitted photonbull Ephoton = E2 ndash E1 and Ephoton = hfbull Ephoton = -15 eV ndash (-136 eV) = 121 eVbull Ephoton = 121 eV = hf (h = 414 x 10-15 eVs )bull f = 121 eV divide 414 x 10-15 eVs = bull Frequency f = 292 x 1015 Hzbull Is this visible light Use c = lf to find the wavelengthbull wavelength l = 102 x 10-7 = 102 nmbull This is NOT visible light- it is UV
Hydrogen EmissionThe energy of the electron is given by
E =
1Find the Energy of the Hydrogen electron from n = 1 to n = 72 Find the Energy of each photon emitted (Ephoton = DE) for these
transitions4 to 1 5 to 2 6 to 3 7 to 43 to 1 4 to 2 5 to 3 6 to 42 to 1 3 to 2 4 to 3 5 to 43 Find the wavelength for each of those photons and determine
what type of electromagnetic wave they are
2neV613
Light behaves like a wave AND like a particle
The first clear demonstration of the particle-like behavior of light was in
The Photoelectric Effect
Albert Einstein won the Nobel Prize in Physics for his explanation of the Photoelectric Effect
Electromagnetic waves striking a metal surface can liberate electrons from its surface
The photons must have enough energy (high enough frequency) for this effect to occur
The energy of the ldquophotoelectronsrdquo liberated from the surface depends on the frequency of the photon
Increasing the intensity (brightness) of the light increases the number of photoelectrons emitted but not the energy of each electron
The Photoelectric
Effect
When will Photoelectrons be produced
Now you try someIf the threshold wavelength for a particular metal is 320 nm
what is the metalrsquos work function
First find the threshold frequency using c = lf Threshold frequency fo = 938 x 1014 Hz
Now find the work-function hfo = Wo
Wo = 388 eV
What if a 450 nm light hit a surface with a work function of 236 eV What will be the kinetic energy of the photoelectron
First find the frequency of the 450 nm lightf = 667 x 1014 HzNow using conservation of energyhf = Wo + Kinetic energySo K = hf ndash WoK = 040 eV
- Quantum Physics
- Slide 2
- What makes one atom different from another
- What makes one atom different from another (2)
- Atomic Spectra
- Atomic Spectra (2)
- Atomic Spectra (3)
- Slide 8
- Slide 9
- The Hydrogen Atom ONE electron
- Now you try onehellip
- Hydrogen Emission
- Slide 13
- Light behaves like a wave AND like a particle
- Slide 15
- Slide 16
- Slide 17
- Now you try some
- Slide 19
- Slide 20
-
Atomic Spectra
bull There are discrete energy levels for each electron in each atom (quantum mechanics)
bull Absorption of energy results in a transitions to a higher energy level
bull A transition back to a lower level produces a photon of light
bull The frequency of the emitted photon is determined by the difference in the energy levels
Ephoton = hf = E2 ndash E1
bull Each frequency is a different color
Atomic Spectra
bull Since the electrons levels are unique for each element each element produces a unique spectra of colors when supplied energy
Spectra for Neon
Atomic Spectra
bull each element produces a unique spectra of colors viewed through a diffraction grating
Spectra for Neon
The incandescence from the elements occurs when solid particles are heated in the flame to extremely high temperatures This releases excess energy in the form of light
The higher the temperature the shorter the wavelength at which light is emitted and the nearer it tends toward the blue end of the colored spectrum
This is why blue colored fireworks are so hard to synthesize as they only occur at very high temperatures
Metal Color
Strontium Red
Copper Blue
Barium Green
Sodium YellowOrange
Calcium Orange
Gold Iron
The Hydrogen AtomONE
electron
The frequency of the emitted photon is determined by the difference in the energy levelsEphoton = hf = E2 ndash E1
Now you try onehellipbull Get out your calculatorsbull The energized electron in Hydrogen makes a transition from n
= 3 with an energy of -15 eV down to its ground state where its energy is -136 eV
What is the frequency of the emitted photonbull Ephoton = E2 ndash E1 and Ephoton = hfbull Ephoton = -15 eV ndash (-136 eV) = 121 eVbull Ephoton = 121 eV = hf (h = 414 x 10-15 eVs )bull f = 121 eV divide 414 x 10-15 eVs = bull Frequency f = 292 x 1015 Hzbull Is this visible light Use c = lf to find the wavelengthbull wavelength l = 102 x 10-7 = 102 nmbull This is NOT visible light- it is UV
Hydrogen EmissionThe energy of the electron is given by
E =
1Find the Energy of the Hydrogen electron from n = 1 to n = 72 Find the Energy of each photon emitted (Ephoton = DE) for these
transitions4 to 1 5 to 2 6 to 3 7 to 43 to 1 4 to 2 5 to 3 6 to 42 to 1 3 to 2 4 to 3 5 to 43 Find the wavelength for each of those photons and determine
what type of electromagnetic wave they are
2neV613
Light behaves like a wave AND like a particle
The first clear demonstration of the particle-like behavior of light was in
The Photoelectric Effect
Albert Einstein won the Nobel Prize in Physics for his explanation of the Photoelectric Effect
Electromagnetic waves striking a metal surface can liberate electrons from its surface
The photons must have enough energy (high enough frequency) for this effect to occur
The energy of the ldquophotoelectronsrdquo liberated from the surface depends on the frequency of the photon
Increasing the intensity (brightness) of the light increases the number of photoelectrons emitted but not the energy of each electron
The Photoelectric
Effect
When will Photoelectrons be produced
Now you try someIf the threshold wavelength for a particular metal is 320 nm
what is the metalrsquos work function
First find the threshold frequency using c = lf Threshold frequency fo = 938 x 1014 Hz
Now find the work-function hfo = Wo
Wo = 388 eV
What if a 450 nm light hit a surface with a work function of 236 eV What will be the kinetic energy of the photoelectron
First find the frequency of the 450 nm lightf = 667 x 1014 HzNow using conservation of energyhf = Wo + Kinetic energySo K = hf ndash WoK = 040 eV
- Quantum Physics
- Slide 2
- What makes one atom different from another
- What makes one atom different from another (2)
- Atomic Spectra
- Atomic Spectra (2)
- Atomic Spectra (3)
- Slide 8
- Slide 9
- The Hydrogen Atom ONE electron
- Now you try onehellip
- Hydrogen Emission
- Slide 13
- Light behaves like a wave AND like a particle
- Slide 15
- Slide 16
- Slide 17
- Now you try some
- Slide 19
- Slide 20
-
Atomic Spectra
bull Since the electrons levels are unique for each element each element produces a unique spectra of colors when supplied energy
Spectra for Neon
Atomic Spectra
bull each element produces a unique spectra of colors viewed through a diffraction grating
Spectra for Neon
The incandescence from the elements occurs when solid particles are heated in the flame to extremely high temperatures This releases excess energy in the form of light
The higher the temperature the shorter the wavelength at which light is emitted and the nearer it tends toward the blue end of the colored spectrum
This is why blue colored fireworks are so hard to synthesize as they only occur at very high temperatures
Metal Color
Strontium Red
Copper Blue
Barium Green
Sodium YellowOrange
Calcium Orange
Gold Iron
The Hydrogen AtomONE
electron
The frequency of the emitted photon is determined by the difference in the energy levelsEphoton = hf = E2 ndash E1
Now you try onehellipbull Get out your calculatorsbull The energized electron in Hydrogen makes a transition from n
= 3 with an energy of -15 eV down to its ground state where its energy is -136 eV
What is the frequency of the emitted photonbull Ephoton = E2 ndash E1 and Ephoton = hfbull Ephoton = -15 eV ndash (-136 eV) = 121 eVbull Ephoton = 121 eV = hf (h = 414 x 10-15 eVs )bull f = 121 eV divide 414 x 10-15 eVs = bull Frequency f = 292 x 1015 Hzbull Is this visible light Use c = lf to find the wavelengthbull wavelength l = 102 x 10-7 = 102 nmbull This is NOT visible light- it is UV
Hydrogen EmissionThe energy of the electron is given by
E =
1Find the Energy of the Hydrogen electron from n = 1 to n = 72 Find the Energy of each photon emitted (Ephoton = DE) for these
transitions4 to 1 5 to 2 6 to 3 7 to 43 to 1 4 to 2 5 to 3 6 to 42 to 1 3 to 2 4 to 3 5 to 43 Find the wavelength for each of those photons and determine
what type of electromagnetic wave they are
2neV613
Light behaves like a wave AND like a particle
The first clear demonstration of the particle-like behavior of light was in
The Photoelectric Effect
Albert Einstein won the Nobel Prize in Physics for his explanation of the Photoelectric Effect
Electromagnetic waves striking a metal surface can liberate electrons from its surface
The photons must have enough energy (high enough frequency) for this effect to occur
The energy of the ldquophotoelectronsrdquo liberated from the surface depends on the frequency of the photon
Increasing the intensity (brightness) of the light increases the number of photoelectrons emitted but not the energy of each electron
The Photoelectric
Effect
When will Photoelectrons be produced
Now you try someIf the threshold wavelength for a particular metal is 320 nm
what is the metalrsquos work function
First find the threshold frequency using c = lf Threshold frequency fo = 938 x 1014 Hz
Now find the work-function hfo = Wo
Wo = 388 eV
What if a 450 nm light hit a surface with a work function of 236 eV What will be the kinetic energy of the photoelectron
First find the frequency of the 450 nm lightf = 667 x 1014 HzNow using conservation of energyhf = Wo + Kinetic energySo K = hf ndash WoK = 040 eV
- Quantum Physics
- Slide 2
- What makes one atom different from another
- What makes one atom different from another (2)
- Atomic Spectra
- Atomic Spectra (2)
- Atomic Spectra (3)
- Slide 8
- Slide 9
- The Hydrogen Atom ONE electron
- Now you try onehellip
- Hydrogen Emission
- Slide 13
- Light behaves like a wave AND like a particle
- Slide 15
- Slide 16
- Slide 17
- Now you try some
- Slide 19
- Slide 20
-
Atomic Spectra
bull each element produces a unique spectra of colors viewed through a diffraction grating
Spectra for Neon
The incandescence from the elements occurs when solid particles are heated in the flame to extremely high temperatures This releases excess energy in the form of light
The higher the temperature the shorter the wavelength at which light is emitted and the nearer it tends toward the blue end of the colored spectrum
This is why blue colored fireworks are so hard to synthesize as they only occur at very high temperatures
Metal Color
Strontium Red
Copper Blue
Barium Green
Sodium YellowOrange
Calcium Orange
Gold Iron
The Hydrogen AtomONE
electron
The frequency of the emitted photon is determined by the difference in the energy levelsEphoton = hf = E2 ndash E1
Now you try onehellipbull Get out your calculatorsbull The energized electron in Hydrogen makes a transition from n
= 3 with an energy of -15 eV down to its ground state where its energy is -136 eV
What is the frequency of the emitted photonbull Ephoton = E2 ndash E1 and Ephoton = hfbull Ephoton = -15 eV ndash (-136 eV) = 121 eVbull Ephoton = 121 eV = hf (h = 414 x 10-15 eVs )bull f = 121 eV divide 414 x 10-15 eVs = bull Frequency f = 292 x 1015 Hzbull Is this visible light Use c = lf to find the wavelengthbull wavelength l = 102 x 10-7 = 102 nmbull This is NOT visible light- it is UV
Hydrogen EmissionThe energy of the electron is given by
E =
1Find the Energy of the Hydrogen electron from n = 1 to n = 72 Find the Energy of each photon emitted (Ephoton = DE) for these
transitions4 to 1 5 to 2 6 to 3 7 to 43 to 1 4 to 2 5 to 3 6 to 42 to 1 3 to 2 4 to 3 5 to 43 Find the wavelength for each of those photons and determine
what type of electromagnetic wave they are
2neV613
Light behaves like a wave AND like a particle
The first clear demonstration of the particle-like behavior of light was in
The Photoelectric Effect
Albert Einstein won the Nobel Prize in Physics for his explanation of the Photoelectric Effect
Electromagnetic waves striking a metal surface can liberate electrons from its surface
The photons must have enough energy (high enough frequency) for this effect to occur
The energy of the ldquophotoelectronsrdquo liberated from the surface depends on the frequency of the photon
Increasing the intensity (brightness) of the light increases the number of photoelectrons emitted but not the energy of each electron
The Photoelectric
Effect
When will Photoelectrons be produced
Now you try someIf the threshold wavelength for a particular metal is 320 nm
what is the metalrsquos work function
First find the threshold frequency using c = lf Threshold frequency fo = 938 x 1014 Hz
Now find the work-function hfo = Wo
Wo = 388 eV
What if a 450 nm light hit a surface with a work function of 236 eV What will be the kinetic energy of the photoelectron
First find the frequency of the 450 nm lightf = 667 x 1014 HzNow using conservation of energyhf = Wo + Kinetic energySo K = hf ndash WoK = 040 eV
- Quantum Physics
- Slide 2
- What makes one atom different from another
- What makes one atom different from another (2)
- Atomic Spectra
- Atomic Spectra (2)
- Atomic Spectra (3)
- Slide 8
- Slide 9
- The Hydrogen Atom ONE electron
- Now you try onehellip
- Hydrogen Emission
- Slide 13
- Light behaves like a wave AND like a particle
- Slide 15
- Slide 16
- Slide 17
- Now you try some
- Slide 19
- Slide 20
-
The incandescence from the elements occurs when solid particles are heated in the flame to extremely high temperatures This releases excess energy in the form of light
The higher the temperature the shorter the wavelength at which light is emitted and the nearer it tends toward the blue end of the colored spectrum
This is why blue colored fireworks are so hard to synthesize as they only occur at very high temperatures
Metal Color
Strontium Red
Copper Blue
Barium Green
Sodium YellowOrange
Calcium Orange
Gold Iron
The Hydrogen AtomONE
electron
The frequency of the emitted photon is determined by the difference in the energy levelsEphoton = hf = E2 ndash E1
Now you try onehellipbull Get out your calculatorsbull The energized electron in Hydrogen makes a transition from n
= 3 with an energy of -15 eV down to its ground state where its energy is -136 eV
What is the frequency of the emitted photonbull Ephoton = E2 ndash E1 and Ephoton = hfbull Ephoton = -15 eV ndash (-136 eV) = 121 eVbull Ephoton = 121 eV = hf (h = 414 x 10-15 eVs )bull f = 121 eV divide 414 x 10-15 eVs = bull Frequency f = 292 x 1015 Hzbull Is this visible light Use c = lf to find the wavelengthbull wavelength l = 102 x 10-7 = 102 nmbull This is NOT visible light- it is UV
Hydrogen EmissionThe energy of the electron is given by
E =
1Find the Energy of the Hydrogen electron from n = 1 to n = 72 Find the Energy of each photon emitted (Ephoton = DE) for these
transitions4 to 1 5 to 2 6 to 3 7 to 43 to 1 4 to 2 5 to 3 6 to 42 to 1 3 to 2 4 to 3 5 to 43 Find the wavelength for each of those photons and determine
what type of electromagnetic wave they are
2neV613
Light behaves like a wave AND like a particle
The first clear demonstration of the particle-like behavior of light was in
The Photoelectric Effect
Albert Einstein won the Nobel Prize in Physics for his explanation of the Photoelectric Effect
Electromagnetic waves striking a metal surface can liberate electrons from its surface
The photons must have enough energy (high enough frequency) for this effect to occur
The energy of the ldquophotoelectronsrdquo liberated from the surface depends on the frequency of the photon
Increasing the intensity (brightness) of the light increases the number of photoelectrons emitted but not the energy of each electron
The Photoelectric
Effect
When will Photoelectrons be produced
Now you try someIf the threshold wavelength for a particular metal is 320 nm
what is the metalrsquos work function
First find the threshold frequency using c = lf Threshold frequency fo = 938 x 1014 Hz
Now find the work-function hfo = Wo
Wo = 388 eV
What if a 450 nm light hit a surface with a work function of 236 eV What will be the kinetic energy of the photoelectron
First find the frequency of the 450 nm lightf = 667 x 1014 HzNow using conservation of energyhf = Wo + Kinetic energySo K = hf ndash WoK = 040 eV
- Quantum Physics
- Slide 2
- What makes one atom different from another
- What makes one atom different from another (2)
- Atomic Spectra
- Atomic Spectra (2)
- Atomic Spectra (3)
- Slide 8
- Slide 9
- The Hydrogen Atom ONE electron
- Now you try onehellip
- Hydrogen Emission
- Slide 13
- Light behaves like a wave AND like a particle
- Slide 15
- Slide 16
- Slide 17
- Now you try some
- Slide 19
- Slide 20
-
The Hydrogen AtomONE
electron
The frequency of the emitted photon is determined by the difference in the energy levelsEphoton = hf = E2 ndash E1
Now you try onehellipbull Get out your calculatorsbull The energized electron in Hydrogen makes a transition from n
= 3 with an energy of -15 eV down to its ground state where its energy is -136 eV
What is the frequency of the emitted photonbull Ephoton = E2 ndash E1 and Ephoton = hfbull Ephoton = -15 eV ndash (-136 eV) = 121 eVbull Ephoton = 121 eV = hf (h = 414 x 10-15 eVs )bull f = 121 eV divide 414 x 10-15 eVs = bull Frequency f = 292 x 1015 Hzbull Is this visible light Use c = lf to find the wavelengthbull wavelength l = 102 x 10-7 = 102 nmbull This is NOT visible light- it is UV
Hydrogen EmissionThe energy of the electron is given by
E =
1Find the Energy of the Hydrogen electron from n = 1 to n = 72 Find the Energy of each photon emitted (Ephoton = DE) for these
transitions4 to 1 5 to 2 6 to 3 7 to 43 to 1 4 to 2 5 to 3 6 to 42 to 1 3 to 2 4 to 3 5 to 43 Find the wavelength for each of those photons and determine
what type of electromagnetic wave they are
2neV613
Light behaves like a wave AND like a particle
The first clear demonstration of the particle-like behavior of light was in
The Photoelectric Effect
Albert Einstein won the Nobel Prize in Physics for his explanation of the Photoelectric Effect
Electromagnetic waves striking a metal surface can liberate electrons from its surface
The photons must have enough energy (high enough frequency) for this effect to occur
The energy of the ldquophotoelectronsrdquo liberated from the surface depends on the frequency of the photon
Increasing the intensity (brightness) of the light increases the number of photoelectrons emitted but not the energy of each electron
The Photoelectric
Effect
When will Photoelectrons be produced
Now you try someIf the threshold wavelength for a particular metal is 320 nm
what is the metalrsquos work function
First find the threshold frequency using c = lf Threshold frequency fo = 938 x 1014 Hz
Now find the work-function hfo = Wo
Wo = 388 eV
What if a 450 nm light hit a surface with a work function of 236 eV What will be the kinetic energy of the photoelectron
First find the frequency of the 450 nm lightf = 667 x 1014 HzNow using conservation of energyhf = Wo + Kinetic energySo K = hf ndash WoK = 040 eV
- Quantum Physics
- Slide 2
- What makes one atom different from another
- What makes one atom different from another (2)
- Atomic Spectra
- Atomic Spectra (2)
- Atomic Spectra (3)
- Slide 8
- Slide 9
- The Hydrogen Atom ONE electron
- Now you try onehellip
- Hydrogen Emission
- Slide 13
- Light behaves like a wave AND like a particle
- Slide 15
- Slide 16
- Slide 17
- Now you try some
- Slide 19
- Slide 20
-
Now you try onehellipbull Get out your calculatorsbull The energized electron in Hydrogen makes a transition from n
= 3 with an energy of -15 eV down to its ground state where its energy is -136 eV
What is the frequency of the emitted photonbull Ephoton = E2 ndash E1 and Ephoton = hfbull Ephoton = -15 eV ndash (-136 eV) = 121 eVbull Ephoton = 121 eV = hf (h = 414 x 10-15 eVs )bull f = 121 eV divide 414 x 10-15 eVs = bull Frequency f = 292 x 1015 Hzbull Is this visible light Use c = lf to find the wavelengthbull wavelength l = 102 x 10-7 = 102 nmbull This is NOT visible light- it is UV
Hydrogen EmissionThe energy of the electron is given by
E =
1Find the Energy of the Hydrogen electron from n = 1 to n = 72 Find the Energy of each photon emitted (Ephoton = DE) for these
transitions4 to 1 5 to 2 6 to 3 7 to 43 to 1 4 to 2 5 to 3 6 to 42 to 1 3 to 2 4 to 3 5 to 43 Find the wavelength for each of those photons and determine
what type of electromagnetic wave they are
2neV613
Light behaves like a wave AND like a particle
The first clear demonstration of the particle-like behavior of light was in
The Photoelectric Effect
Albert Einstein won the Nobel Prize in Physics for his explanation of the Photoelectric Effect
Electromagnetic waves striking a metal surface can liberate electrons from its surface
The photons must have enough energy (high enough frequency) for this effect to occur
The energy of the ldquophotoelectronsrdquo liberated from the surface depends on the frequency of the photon
Increasing the intensity (brightness) of the light increases the number of photoelectrons emitted but not the energy of each electron
The Photoelectric
Effect
When will Photoelectrons be produced
Now you try someIf the threshold wavelength for a particular metal is 320 nm
what is the metalrsquos work function
First find the threshold frequency using c = lf Threshold frequency fo = 938 x 1014 Hz
Now find the work-function hfo = Wo
Wo = 388 eV
What if a 450 nm light hit a surface with a work function of 236 eV What will be the kinetic energy of the photoelectron
First find the frequency of the 450 nm lightf = 667 x 1014 HzNow using conservation of energyhf = Wo + Kinetic energySo K = hf ndash WoK = 040 eV
- Quantum Physics
- Slide 2
- What makes one atom different from another
- What makes one atom different from another (2)
- Atomic Spectra
- Atomic Spectra (2)
- Atomic Spectra (3)
- Slide 8
- Slide 9
- The Hydrogen Atom ONE electron
- Now you try onehellip
- Hydrogen Emission
- Slide 13
- Light behaves like a wave AND like a particle
- Slide 15
- Slide 16
- Slide 17
- Now you try some
- Slide 19
- Slide 20
-
Hydrogen EmissionThe energy of the electron is given by
E =
1Find the Energy of the Hydrogen electron from n = 1 to n = 72 Find the Energy of each photon emitted (Ephoton = DE) for these
transitions4 to 1 5 to 2 6 to 3 7 to 43 to 1 4 to 2 5 to 3 6 to 42 to 1 3 to 2 4 to 3 5 to 43 Find the wavelength for each of those photons and determine
what type of electromagnetic wave they are
2neV613
Light behaves like a wave AND like a particle
The first clear demonstration of the particle-like behavior of light was in
The Photoelectric Effect
Albert Einstein won the Nobel Prize in Physics for his explanation of the Photoelectric Effect
Electromagnetic waves striking a metal surface can liberate electrons from its surface
The photons must have enough energy (high enough frequency) for this effect to occur
The energy of the ldquophotoelectronsrdquo liberated from the surface depends on the frequency of the photon
Increasing the intensity (brightness) of the light increases the number of photoelectrons emitted but not the energy of each electron
The Photoelectric
Effect
When will Photoelectrons be produced
Now you try someIf the threshold wavelength for a particular metal is 320 nm
what is the metalrsquos work function
First find the threshold frequency using c = lf Threshold frequency fo = 938 x 1014 Hz
Now find the work-function hfo = Wo
Wo = 388 eV
What if a 450 nm light hit a surface with a work function of 236 eV What will be the kinetic energy of the photoelectron
First find the frequency of the 450 nm lightf = 667 x 1014 HzNow using conservation of energyhf = Wo + Kinetic energySo K = hf ndash WoK = 040 eV
- Quantum Physics
- Slide 2
- What makes one atom different from another
- What makes one atom different from another (2)
- Atomic Spectra
- Atomic Spectra (2)
- Atomic Spectra (3)
- Slide 8
- Slide 9
- The Hydrogen Atom ONE electron
- Now you try onehellip
- Hydrogen Emission
- Slide 13
- Light behaves like a wave AND like a particle
- Slide 15
- Slide 16
- Slide 17
- Now you try some
- Slide 19
- Slide 20
-
Light behaves like a wave AND like a particle
The first clear demonstration of the particle-like behavior of light was in
The Photoelectric Effect
Albert Einstein won the Nobel Prize in Physics for his explanation of the Photoelectric Effect
Electromagnetic waves striking a metal surface can liberate electrons from its surface
The photons must have enough energy (high enough frequency) for this effect to occur
The energy of the ldquophotoelectronsrdquo liberated from the surface depends on the frequency of the photon
Increasing the intensity (brightness) of the light increases the number of photoelectrons emitted but not the energy of each electron
The Photoelectric
Effect
When will Photoelectrons be produced
Now you try someIf the threshold wavelength for a particular metal is 320 nm
what is the metalrsquos work function
First find the threshold frequency using c = lf Threshold frequency fo = 938 x 1014 Hz
Now find the work-function hfo = Wo
Wo = 388 eV
What if a 450 nm light hit a surface with a work function of 236 eV What will be the kinetic energy of the photoelectron
First find the frequency of the 450 nm lightf = 667 x 1014 HzNow using conservation of energyhf = Wo + Kinetic energySo K = hf ndash WoK = 040 eV
- Quantum Physics
- Slide 2
- What makes one atom different from another
- What makes one atom different from another (2)
- Atomic Spectra
- Atomic Spectra (2)
- Atomic Spectra (3)
- Slide 8
- Slide 9
- The Hydrogen Atom ONE electron
- Now you try onehellip
- Hydrogen Emission
- Slide 13
- Light behaves like a wave AND like a particle
- Slide 15
- Slide 16
- Slide 17
- Now you try some
- Slide 19
- Slide 20
-
Electromagnetic waves striking a metal surface can liberate electrons from its surface
The photons must have enough energy (high enough frequency) for this effect to occur
The energy of the ldquophotoelectronsrdquo liberated from the surface depends on the frequency of the photon
Increasing the intensity (brightness) of the light increases the number of photoelectrons emitted but not the energy of each electron
The Photoelectric
Effect
When will Photoelectrons be produced
Now you try someIf the threshold wavelength for a particular metal is 320 nm
what is the metalrsquos work function
First find the threshold frequency using c = lf Threshold frequency fo = 938 x 1014 Hz
Now find the work-function hfo = Wo
Wo = 388 eV
What if a 450 nm light hit a surface with a work function of 236 eV What will be the kinetic energy of the photoelectron
First find the frequency of the 450 nm lightf = 667 x 1014 HzNow using conservation of energyhf = Wo + Kinetic energySo K = hf ndash WoK = 040 eV
- Quantum Physics
- Slide 2
- What makes one atom different from another
- What makes one atom different from another (2)
- Atomic Spectra
- Atomic Spectra (2)
- Atomic Spectra (3)
- Slide 8
- Slide 9
- The Hydrogen Atom ONE electron
- Now you try onehellip
- Hydrogen Emission
- Slide 13
- Light behaves like a wave AND like a particle
- Slide 15
- Slide 16
- Slide 17
- Now you try some
- Slide 19
- Slide 20
-
When will Photoelectrons be produced
Now you try someIf the threshold wavelength for a particular metal is 320 nm
what is the metalrsquos work function
First find the threshold frequency using c = lf Threshold frequency fo = 938 x 1014 Hz
Now find the work-function hfo = Wo
Wo = 388 eV
What if a 450 nm light hit a surface with a work function of 236 eV What will be the kinetic energy of the photoelectron
First find the frequency of the 450 nm lightf = 667 x 1014 HzNow using conservation of energyhf = Wo + Kinetic energySo K = hf ndash WoK = 040 eV
- Quantum Physics
- Slide 2
- What makes one atom different from another
- What makes one atom different from another (2)
- Atomic Spectra
- Atomic Spectra (2)
- Atomic Spectra (3)
- Slide 8
- Slide 9
- The Hydrogen Atom ONE electron
- Now you try onehellip
- Hydrogen Emission
- Slide 13
- Light behaves like a wave AND like a particle
- Slide 15
- Slide 16
- Slide 17
- Now you try some
- Slide 19
- Slide 20
-
Now you try someIf the threshold wavelength for a particular metal is 320 nm
what is the metalrsquos work function
First find the threshold frequency using c = lf Threshold frequency fo = 938 x 1014 Hz
Now find the work-function hfo = Wo
Wo = 388 eV
What if a 450 nm light hit a surface with a work function of 236 eV What will be the kinetic energy of the photoelectron
First find the frequency of the 450 nm lightf = 667 x 1014 HzNow using conservation of energyhf = Wo + Kinetic energySo K = hf ndash WoK = 040 eV
- Quantum Physics
- Slide 2
- What makes one atom different from another
- What makes one atom different from another (2)
- Atomic Spectra
- Atomic Spectra (2)
- Atomic Spectra (3)
- Slide 8
- Slide 9
- The Hydrogen Atom ONE electron
- Now you try onehellip
- Hydrogen Emission
- Slide 13
- Light behaves like a wave AND like a particle
- Slide 15
- Slide 16
- Slide 17
- Now you try some
- Slide 19
- Slide 20
-
What if a 450 nm light hit a surface with a work function of 236 eV What will be the kinetic energy of the photoelectron
First find the frequency of the 450 nm lightf = 667 x 1014 HzNow using conservation of energyhf = Wo + Kinetic energySo K = hf ndash WoK = 040 eV
- Quantum Physics
- Slide 2
- What makes one atom different from another
- What makes one atom different from another (2)
- Atomic Spectra
- Atomic Spectra (2)
- Atomic Spectra (3)
- Slide 8
- Slide 9
- The Hydrogen Atom ONE electron
- Now you try onehellip
- Hydrogen Emission
- Slide 13
- Light behaves like a wave AND like a particle
- Slide 15
- Slide 16
- Slide 17
- Now you try some
- Slide 19
- Slide 20
-
- Quantum Physics
- Slide 2
- What makes one atom different from another
- What makes one atom different from another (2)
- Atomic Spectra
- Atomic Spectra (2)
- Atomic Spectra (3)
- Slide 8
- Slide 9
- The Hydrogen Atom ONE electron
- Now you try onehellip
- Hydrogen Emission
- Slide 13
- Light behaves like a wave AND like a particle
- Slide 15
- Slide 16
- Slide 17
- Now you try some
- Slide 19
- Slide 20
-