General Chemistry Principles, Patterns, and Applications, 2011

1. For a 4p subshell, n = 4 and l = 1. The allowed values of the magnetic quantum number,ml, are therefore +1,
3.
0, −1, corresponding to three 4p orbitals. For a 3d subshell, n = 3 and l = 2. The allowed values of the
magnetic quantum number, ml, are therefore +2, +1, 0, −1, −2, corresponding to five 3d orbitals.
1. n = 3, l = 2, ml = 2, ms = +12;n = 3, l = 2, ml = 2, ms = -12
[1] All stable nuclei other than hydrogen also contain one or more neutrons. Because neutrons
have no electrical charge, however, they can be ignored in the following discussion.
6.7 End-of-Chapter Material
A P P L I C A T I ON PR OBLEMS
1. The lamps in street lights use emission of light from excited states of atoms to produce a characteristic glow.
Light is generated by electron bombardment of a metal vapor. Of calcium and strontium, which metal vapor
would you use to produce yellow light? Which metal would you use to produce red light? Calculate the
energy associated with each transition and propose an explanation for the colors of the emitted light.
2. Lasers have useful medical applications because their light is directional (permitting tight focus of the laser
beam for precise cutting), monochromatic, and intense. Carbon dioxide lasers, emitting at a wavelength of
1.06 × 10 4 nm, are typically used in surgery.
a. What are the frequency and energy (in kilojoules per mole) of a photon from a carbon dioxide laser?
b. Why is monochromatic light desirable in a surgical procedure?
c. Biological tissue consists primarily of water, which absorbs electromagnetic radiation in the infrared region of
the spectrum. Suggest a plausible reason for using carbon dioxide lasers in surgery.
3. An excimer (meaning “excited dimer”) laser emits light in the ultraviolet region of the spectrum. An example
of such a laser is krypton fluoride (KrF), which emits light at a wavelength of 248 nm. What is the energy in
joules of a mole of photons emitted from this laser? How much more energetic is a single photon of this
wavelength than a photon from a carbon dioxide laser used in surgery (10,600 nm)?
4. Wavelengths less than 10 nm are needed to “see” objects on an atomic or molecular scale. Such imaging can
be accomplished with an electron microscope, which uses electric and magnetic fields to focus and
accelerate a beam of electrons to a high velocity. Electron microscopy is now a powerful tool in chemical
research. What electron velocity is needed to produce electrons with a wavelength of 4 × 10 −3 nm, which is
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