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Ch.6 - Electronic Structure of Atoms
Chapter 6, Problem 95

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.]

Verified step by step guidance
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Step 1: Identify the relevant equations. The de Broglie wavelength equation is \( \lambda = \frac{h}{p} \), where \( \lambda \) is the wavelength, \( h \) is Planck's constant, and \( p \) is the momentum of the electron. The momentum \( p \) can be expressed as \( p = mv \), where \( m \) is the mass and \( v \) is the velocity of the electron.
Step 2: Relate kinetic energy to velocity. The kinetic energy \( E \) of the electron is given by \( E = \frac{1}{2}mv^2 \). Rearrange this equation to solve for \( v \): \( v = \sqrt{\frac{2E}{m}} \).
Step 3: Calculate the momentum \( p \) using the velocity. Substitute the expression for \( v \) from Step 2 into the momentum equation \( p = mv \) to get \( p = m \sqrt{\frac{2E}{m}} \). Simplify this to \( p = \sqrt{2mE} \).
Step 4: Substitute the expression for momentum \( p \) into the de Broglie wavelength equation. This gives \( \lambda = \frac{h}{\sqrt{2mE}} \).
Step 5: Substitute known values into the equation. Use Planck's constant \( h = 6.626 \times 10^{-34} \text{ J s} \), the mass of an electron \( m = 9.109 \times 10^{-31} \text{ kg} \), and the given kinetic energy \( E = 1.6 \times 10^{-15} \text{ J} \) to calculate \( \lambda \).
Related Practice
Textbook Question

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.

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Textbook Question

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: (e) n = 2, l = 1, ml = 1, ms = -12

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Textbook Question

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?

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Open Question
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.
Textbook Question

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?

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Textbook Question
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 ?
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