Chapter 8

What is light? How fast does it travel in a vacuum?

Define the wavelength and amplitude of a wave. How are these related to the energy of the wave?

Define the frequency of electromagnetic radiation. How is frequency related to wavelength?

What determines the color of light? Describe the difference between red light and blue light.

What determines the color of a colored object? Explain why grass appears green.

Give an approximate range of wavelengths for each type of electromagnetic radlation and summarize the characteristics and/ ot the uses of each. a. Bamma rays b. X-rays c. ultraviolet radiation d. vislble light e. Infrared radiation I. microwave radiation g. radio waves

explain the wave behavior known as interference. Explain the difference between constructive and destructive interference.

. Describe the photoelectric effect. How did experimental observations of this phenomenon differ from the predictions of classical electromagnetic theory?

What is a photon? How is the energy of a photon related to its wavelength? Its frequency?

What is an emission spectrum? How does an emission spectrum of a gas in a discharge tube differ from a white light spectrum?

Describe the Bohr model for the atom. How did the Bohr model account for the emission spectra of atoms?

Explain Heisenberg's uncertainty principle. What paradox is at least partially solved by the uncertainty principle?

Newton's laws of motion are deterministic. Explain this statement.

For each solution to the Schrodinger equation, what can be precisely specified: the electron's energy or its position? Explain.

What is the Schrodinger equation? What is a wave function? How is a wave function related to an orbital?

What are the possible values of the principal quantum number n? What does the principal quantum number determine?

What are the possible values of the magnetic quantum number m? What does the magnetic quantum number determine?

Explain the difference between a plot showing the probability density for an orbital and one showing the radial distribution function.

Make sketches of the general shapes of the \(s, p,\) and \(d\) orbitals.

List the four different sublevels asociated with \(n=4\). Given that only a maximum of two electrons can occupy an orbital, determine the maximum number of electrons that can exist in each sublevel.

Why are atoms usually portrayed as spheres when most orbitals are not spherically shaped?

List these types of electromagnetic radlation in onder of (i) Increasing frequency and (u) decreasing energy per photon. a. gamma rays b. radio waves c. microwaves d. visible light

Calculate the frequency of each wavelength of electromagnetic tadiation. MisseD THis? Read Section 8.2 a. \(6328 \mathrm{nm}\) (wavelength of red light from hellum-neon laser) b. \(\mathrm{SO} 3 \mathrm{nm}\) (wavelength of maximum solar radlation) c. 0.062 nm (a wavelength contained in medical X-rays)

A laser pulse with wavelength 532 nm contains \(3.85 \mathrm{mj}\) of energy. How many photons are in the laser pulse?

Determine the energy of 1 mol of photons for each kind of light. (Assume three significant figures.) MissED This? Read Section \(8.2 ;\) Watch \(\mathrm{KCV} 8.2,\) WE 8.2 a. infrared radiation \((1500 \mathrm{nm})\) b. visible light \((500 \mathrm{nm})\) c. ultraviolet radiation (150 nm)

How much energy is contained in 1 mol of each? a. X-ray photons with a wavelength of \(0.135 \mathrm{nm}\) b. \(\gamma\) -ray photons with a wavelength of \(2.15 \times 10^{-8} \mathrm{nm}\)

What is the de Broglie wavelength of an electron traveling at \(1.35 \times 10^{5} \mathrm{~m} / \mathrm{s} ?\)

Calculate the de Broglie wavelength of a 143 -g baseball traveling at 95 mph. Why is the wave nature of matter not important for a baseball? Mi55ED Thist Read Section 8.4; Watch KCV 8.4

A 0.22 -caliber handgun fires a \(1.9-\mathrm{g}\) bullet at a velocity of \(765 \mathrm{~m} / \mathrm{s}\). Calculate the de Broglie wavelength of the bullet. Is the wave nature of matter slgnificant for bullets?

Which electron is, on average, closer to the nucleus: an electron in \(a\) 2 orbital or an electron in a 3 s orbital? MISSED THIS7 Read Sections 8.5 . 8.6; Watch KCV B. 54

Which electron is, on average, farther from the nucleus: an electron in a 3p orbital or an electron in a \(4 p\) orbital?

According to the quantum-mechanical model for the hydrogen atom, which electron transition produces light with the longer wavelength: \(2 p \longrightarrow 1 s\) or \(3 p \longrightarrow 1 s ?\) MiSSED This? Read Section 8.5; Watch KCV 8.58

According to the quantum-mechanical model for the hydrogen atom, which electron transition produces light with the longer wavelength: \(3 p \longrightarrow 2 s\) or \(4 p \longrightarrow 3 p ?\)

Ultraviolet radiation and radlation of shorter wavelengths can damage biological molecules because these kinds of radlation carry enough energy to break bonds within the molecules. A typical carbon-carbon bond fequires 348 kl / mol to beeak. What is the longest wavelength of radiation with enough energy to break carbon-carbon bonds?

In a technique used for sunface analysis called Auger electron spectroscopy (AES), clectrons are accelerated toward a metal surface, These clectaons cause the emissions of secondary electrons called Augcr electrons-from the metal surface. The kinctic enetgy of the Auger electrons depends on the composition of the surface. The presence of oxygen atoms on the surface sesults in Auger electrons with a kinetic energy of approximately 506 eV. What is the de Broglie wavelength of one of these electrons? $$ \left[\mathrm{KE}-\frac{1}{2} m v^{2} ; 1 \text { electron volt }(\mathrm{eV})-1.602 \times 10^{-19} \mathrm{~J}\right] $$

An X-tay photon of wavelength \(0.989 \mathrm{nm}\) strikes a surface. The emitted electron has a kinetic energy of 969 eV. What is the binding energy of the electron in kj/mol? $$ \left[1 \text { electron volt }(\mathrm{eV})=1.602 \times 10^{-19} \mathrm{~J}\right] $$

The speed of sound in air is \(344 \mathrm{~m} / \mathrm{s}\) at room temperature. The lowest frequency of a large organ pipe is \(30 \mathrm{~s}^{-1}\) and the highest frequency of a piccolo is \(1.5 \times 10^{4} \mathrm{~s}^{-1} .\) Find the difference in wavelength between these two sounds.

A particular laser consumes 150.0 watts of electrical power and produces a stream of \(1.33 \times 10^{19} 1064-\mathrm{nm}\) photons per second. What is the percent efficiency of the laser in converting electrical power to light?

Explain the difference between the Bohr model for the hydroBen atom and the quantum-mechanical model. Is the Bohr model consistent with Heisenberg's uncertainty principle?

Determine whether an interference pattern is observed on the other side of the slits in each experiment. a. An electron beam is aimed at two closely spaced slits. The beam produces only one electron per minute. b. An electron beam is aimed at two closely spaced slits. A light beam is placed at each slit to determine when an electron goes through the slit. c. A high-intensity light beam is aimed at two closely spaced slits. d. A gun is fired at a solid wall containing two closely spaced slits. (Will the bullets that pass through the slits form an Interference pattern on the other side of the solid wall?