Atomic Structure Questions
According to Niels Bohr, what does "n" stand for?
According to Bohr, "n" stands for the orbit or energy level of the electron.
According to Bohr, why do atoms emit light?
According to the Bohr model, atoms emit light because excited electrons are returning to lower energy states, emitting the energy difference. This energy always has a specific wavelength because the electrons can only exist in set orbits.
Describe the Bohr model of an atom.
In the Bohr model of the atom, the nucleus is at the center of the atom with electrons orbiting it at set distances, similar to the way planets orbit the Sun.
Describe the nuclear model of the atom
In the nuclear model of the atom, protons (and neutrons) are housed in a small, dense nucleus. Electrons surround the nucleus in an area of mostly empty space.
Why does the dual nature of matter make it difficult to observe very small particles like electrons?
Observing these particles changes their momentum, so position and momentum cannot be simultaneously known.
Define "ground state".
The ground state is the lowest energy state that an electron can reside.
Which of the following transitions would produce the greatest amount of energy: 2→1, 3→2, or 4→3?
2→1
Which of the following transitions would produce the greatest amount of energy: 1→2, 3→1, or 2→1?
3→1
What is an emission spectrum?
An emission spectrum is the frequencies of light emitted from an atom.
How can emission spectra be used to identify unknown elements?
Because each element has a different number of protons and electrons, their "n" values differ from each other. Each element thus produces its own emission spectra which allows scientists to identify elements.
How do electrons get to an excited state?
Electrons get to an excited state by absorbing the energy of a photon.
How did emission spectra of gases affect our understanding of atomic structure?
Emission spectra showed that electrons only emit radiation at certain wavelengths and frequencies, and, therefore, energy levels. This indicating that electrons could be found in specific energy levels or orbits.
Define "excited state".
Excited states are any energy state above the ground state.
Using wavelengths emitted from a hydrogen atom, a student finds that the value of "n" in the Balmer Series of hydrogen is 4.5. Is this value accurate? Justify your answer.
No, this is not accurate. "n" can only be whole numbers; there are no half-levels in the Bohr model of the atom
Why did scientists need to improve upon the Bohr model?
The Bohr model was only able to explain the emission spectrum of hydrogen.
Explain how the double slit experiment has impacted our understanding of atomic structure.
The double slit experiment illustrates that electrons are both a particle and a wave. It also shows that we cannot determine the path of an individual electron but we can determine the probable distribution of electrons.
What is the Heisenberg Uncertainty Principle?
The position and momentum of an electron cannot be known simultaneously.
