The Modern Atomic Theory
Electrons orbit the nucleus in specific, defined paths. Each path has a specified energy.
Bohr model
Atoms are indivisible spheres.
Dalton model
Which statement about Niels Bohr's atomic model is true?
Each orbit has a specific energy level.
The Bohr model of the atom explained why emission spectra are discrete. It could also be used to explain the photoelectric effect. Which is a correct explanation of the photoelectric effect according to the model?
Electrons need specific amounts of energy to "jump" off an atom and be emitted.
Which observation provided Albert Einstein the clue that he needed to explain the photoelectric effect?
Energy of electrons depends on light's frequency, not intensity
Which statement describes a major drawback of the Bohr model that caused scientists to replace it?
It contradicted the Heisenberg uncertainty principle.
Which statement about the electron-cloud model is true?
It is the currently accepted atomic model.
According to the Bohr model of an atom, what happens when an electron moves from the second energy level to the third energy level and then back to the second energy level?
NOT Energy is released and then absorbed to form an absorption line.
The diagram shows Niels Bohr's model of an atom. What happens when the electron moves from the first energy level to the second energy level?
NOT Energy is released, and an emission line is produced.
Light of a certain energy shines on a metal and causes electrons to be emitted. Based on the research of Albert Einstein, what change would most likely result in stopping the emission of electrons from this metal?
NOT a decrease in the intensity of the light
A change in which property of light will have no effect on whether or not the photoelectric effect occurs?
NOT wavelength
Which statement about the electron-cloud model is true?
NOT: It specifies the location and momentum of an electron.
Which scientist is known for developing the planetary model of the atom?
Niels Bohr
How did Niels Bohr describe electrons in his atomic model?
They orbit the central nucleus in discrete paths.
Kumar is producing the photoelectric effect by using red light. He wants to increase the energy of emitted electrons. Based on the research of Albert Einstein, what is the best way for him to do this?
Use a different colored light that has a higher frequency.
The modern-day quantum model of the atom is better than John Dalton's model because it
answers many questions about atoms.
This flow chart shows the amount of energy that is emitted by each type of light. ultraviolet > blue light > yellow light > red light (maximum energy) (minimum energy) In an experiment, shining which type of light on a strip of metal would be least likely to produce the photoelectric effect?
bright red light
An electron's position cannot be known precisely. Only its probability of being in a certain location can be known.
electron cloud model
Which atomic model states that it is impossible to know the exact location of electrons around the nucleus?
electron-cloud model
A hydrogen electron is elevated from level 1 to level 2. Another electron is elevated from level 2 to level 4. The transition requiring the greatest energy change is
level 2 to level 4
Light is emitted by electrons when they drop from one energy level to a lower level. Which transition results in the emission of light with the greatest energy?
level 4 to level 2
Light shining on a strip of metal can dislodge electrons. Do you think this is more consistent with light being made up of waves or of particles?
particles
Electrons are embedded in a mass of positively charged matter.
plum pudding model
Blue light waves have more energy than red light waves. Which of these situations most likely produces a photoelectric effect? You may assume that the same metal is used in each situation. Check all that apply.
shining dim blue light on a strip of metal; shining bright blue light on a strip of metal