Problem 77c
Identify the specific element that corresponds to each of the following electron configurations and indicate the number of unpaired electrons for each: (c) 3Ar44s13d5
Problem 77d
Identify the specific element that corresponds to each of the following electron configurations and indicate the number of unpaired electrons for each: (d) 3Kr45s24d105p4.
Problem 78
(a) What does the term paramagnetism mean? (b) How can one determine experimentally whether a substance is paramagnetic? (c) Which of the following ions would you expect to be paramagnetic: O2+ , N22 -, Li2+ , O22 - ? For those ions that are paramagnetic, determine the number of unpaired electrons.
Problem 79
The following do not represent valid ground-state electron configurations for an atom either because they violate the Pauli exclusion principle or because orbitals are not filled in order of increasing energy. Indicate which of these two principles is violated in each example. (a) [Ne]3s23p63d5 (b) [Xe]6s3 (c) 1s23s1.
Problem 80b
The following electron configurations represent excited states. Identify the element and write its ground-state condensed electron configuration. (b) 3Ne43s13p44p1.
Problem 81a1
Consider the two waves shown here, which we will consider to represent two electromagnetic radiations: (a) What is the wavelength of wave A?
Problem 81b1
Consider the two waves shown here, which we will consider to represent two electromagnetic radiations: (b) What is the frequency of wave A?
Problem 82b
If a sample of calcium chloride is introduced into a nonluminous flame, the color of the flame turns to orange ('flame test'). The light is emitted because calcium atoms become excited; their return to the ground state results in light emission. (b) What is the energy of 1.00 mol of these photons (a mole of photons is called an Einstein)?
Problem 82c
If a sample of calcium chloride is introduced into a nonluminous flame, the color of the flame turns to orange (“flame test”). The light is emitted because calcium atoms become excited; their return to the ground state results in light emission. (c) Calculate the energy gap between the excited and ground states for the calcium atom.
Problem 83a
Certain elements emit light of a specific wavelength when they are burned or heated in a non-luminous flame. Historically, chemists used such emission wavelengths to determine whether specific elements were present in a sample. Some characteristic wavelengths for a few of the elements are given in the following table: Ag 328.1 nm Fe 372.0 nm Au 267.6 nm K 404.7 nm Ba 455.4 nm Mg 285.2 nm Ca 422.7 nm Na 589.6 nm Cu 324.8 nm Ni 341.5 nm (a) Determine which of these emissions occur in the ultraviolet part of the spectrum.
Problem 83c
Certain elements emit light of a specific wavelength when they are burned or heated in a non-luminous flame. Historically, chemists used such emission wavelengths to determine whether specific elements were present in a sample. Some characteristic wavelengths for a few of the elements are given in the following table: Ag 328.1 nm Fe 372.0 nm Au 267.6 nm K 404.7 nm Ba 455.4 nm Mg 285.2 nm Ca 422.7 nm Na 589.6 nm Cu 324.8 nm Ni 341.5 nm (c) When burned, a sample of an unknown substance is found to emit light of frequency 6.58 × 1014 s-1. Which of these elements is probably in the sample?
Problem 84
In January 2006, the New Horizons space probe was launched from Earth with the mission to perform a flyby study of Pluto. The arrival at the dwarf planet was estimated to happen after nine years, in 2015. The distance between Earth and Pluto varies depending on the location of the planets in their orbits, but at their closest, the distance is 4.2 billion kilometers (2.6 billion miles). Calculate the minimum amount of time it takes for a transmitted signal from Pluto to reach the Earth.
- Is the observation that UV-B radiation is a more important cause of sunburn in humans than UV-A radiation consistent with the answer to part (c)?
Problem 85
Problem 86
The watt is the derived SI unit of power, the measure of energy per unit time: 1 W = 1 J>s. A semiconductor laser in a DVD player has an output wavelength of 650 nm and a power level of 5.0 mW. How many photons strike the DVD surface during the playing of a DVD 90 minutes in length?
Problem 88a
In an experiment to study the photoelectric effect, a scientist measures the kinetic energy of ejected electrons as a function of the frequency of radiation hitting a metal surface. She obtains the following plot. The point labeled 'n0' corresponds to light with a wavelength of 542 nm. (a) What is the value of n0 in s - 1?
Problem 89a
Consider a transition in which the electron of a hydrogen atom is excited from n = 1 to n = ∞. (a) What is the end result of this transition?
Problem 89b
Consider a transition in which the electron of a hydrogen atom is excited from n = 1 to n = ∞. (b) What is the wavelength of light that must be absorbed to accomplish this process?
Problem 89c
Consider a transition in which the electron of a hydrogen atom is excited from n = 1 to n = ∞. (c) What will occur if light with a shorter wavelength than that in part (b) is used to excite the hydrogen atom?
Problem 89d
Consider a transition in which the electron of a hydrogen atom is excited from n = 1 to n = ∞. (d) How are the results of parts (b) and (c) related to the plot shown in Exercise 6.88?
Problem 90c
The human retina has three types of receptor cones, each sensitive to a different range of wavelengths of visible light, as shown in this figure (the colors are merely to differentiate the three curves from one another; they do not indicate the actual colors represented by each curve):
(c) Explain why the sky appears blue even though all wavelengths of solar light are scattered by the atmosphere.
Problem 91a
The series of emission lines of the hydrogen atom for which nf = 3 is called the Paschen series. (a) Determine the region of the electromagnetic spectrum in which the lines of the Paschen series are observed.
Problem 91b
The series of emission lines of the hydrogen atom for which nf = 3 is called the Paschen series. (b) Calculate the wavelengths of the first three lines in the Paschen series—those for which ni = 4, 5, and 6.
Problem 93
Determine whether each of the following sets of quantum numbers for the hydrogen atom are valid. If a set is not valid, indicate which of the quantum numbers has a value that is not valid: (a) n = 3, l = 3, ml = 2, ms = +1/2 (b) n = 4, l = 3, ml = -3, ms = +1/2 (c) n = 3, l = 1, ml = 2, ms = +1/2 (d) n = 5, l = 0, ml = 0, ms = 0 (e) n = 2, l = 1, ml = 1, ms = -1/2
- Bohr’s model can be used for hydrogen-like ions—ions that have only one electron, such as He+ and Li2+. The ground-state energies of B4+, C5+, and N6+ are tabulated as follows: Atom or ion B4+ C5+ N6+ Ground-state energy -5.45 * 10^-17 J -7.85 * 10^-17 J -1.07 * 10^-16 J. By examining these numbers, propose a relationship between the ground-state energy of hydrogen-like systems and the nuclear charge, Z. (Hint: Divide by the ground-state energy of hydrogen, -2.18 * 10^-18 J)
Problem 94
Problem 94a
Bohr's model can be used for hydrogen-like ions—ions that have only one electron, such as He+ and Li2+. (a) Why is the Bohr model applicable to He+ ions but not to neutral He atoms?
- An electron is accelerated through an electric potential to a kinetic energy of 1.6 * 10^-15 J. What is its characteristic wavelength? [Hint: Recall that the kinetic energy of a moving object is E = 1/2 mv^2, where m is the mass of the object and v is the speed of the object.]
Problem 95
- In the television series Star Trek, the transporter beam is a device used to “beam down” people from the Starship Enterprise to another location, such as the surface of a planet. The writers of the show put a “Heisenberg compensator” into the transporter beam mechanism. Explain why such a compensator (which is entirely fictional) would be necessary to get around Heisenberg’s uncertainty principle.
Problem 96
- As discussed in the A Closer Look box on “Measurement and the Uncertainty Principle,” the essence of the uncertainty principle is that we can’t make a measurement without disturbing the system that we are measuring. (b) How is this concept related to the paradox discussed in the Closer Look box on “Thought Experiments and Schrödinger’s Cat”?
Problem 97
Problem 97a
As discussed in the A Closer Look box on 'Measurement and the Uncertainty Principle,' the essence of the uncertainty principle is that we can't make a measurement without disturbing the system that we are measuring. (a) Why can't we measure the position of a subatomic particle without disturbing it?
- Consider the discussion of radial probability functions in 'A Closer Look' in Section 6.6. (a) What is the difference between the probability density as a function of r and the radial probability function as a function of r ?
Problem 98
Ch.6 - Electronic Structure of Atoms