Practice Problems-Test 4

1.A photon has an energy of 5.42 eV. What is the frequency of the photon?
a. 1.31x10¹⁵ Hz  b. 6.63x10¹⁴ Hz  c. 5.42x10¹⁰ Hz  d. 8.17x10³³ Hz

2.Light falling on a metal whose workfunction is 4.08 eV ejects electrons from the surface with a kinetic energy of 1.29 eV. What is the frequency of the light?
a. 4.45x10 ¹⁹ Hz  b. 6.73x10¹⁴ Hz  c. 1.30x10¹⁵  d. 8.95x10^-19 Hz

3. What is the de Broglie wavelength of a 0.50 g bullet traveling with a speed of 320 m/s?
a. 4.14x10^-36 m  b. 2.4x10²³ m  c. 4.1x10^-33 m  d. 0 m

4.The Heisenburg uncertainty principle implies that the momentum and position cannot be accurately determined at the same time. What is the truth this statement?
a. It is true as stated.  b. It is true only if your experiments are not perfect
c. It is true if the particles are not waves.  d. It is definitely not true.

5. A particle of mass 0.35x10^-6 g is trapped in a box of length 1.0x10^-6 m. What is the minimum uncertainty in theparticle's velocity along the length of the box?a. zero  b. 3.0 x 10^-19 m/s   c. 3.210^-7  m/s  d. 1.5 m/s

6.The wave-particle duality refers to the fact that--------can exhibit both wave and particle characteristics.
a. light  b. matter  c. both light and matter  d. nothing

7.An electron has been accelerated from rest through a potential difference of 2.5x10³ V. What is the de Broglie wavelength of the electron?

8.Find the wavelength and the frequency of the n = 4 Balmer line.

9. Write down the eighteen possible sets of four quantum numbers that exit when the principal quantum number is 3.

10. How many electrons can be put into (a) the n = 4 and (b) the n = 5 shell?

11.Determine the radius and energy of  the hydrogen atom in the n=3 state of the Bohr model.

12.Light of 1090 nm wavelength is emitted from a hydrogen discharge tube. If the transitions that produces this emission occurs to the n_f = 3 level, from which level did it originate?

13.Write down the ground state electronic configuration for iron Z=26.

14. Which of the following is not a feature of the Bohr model of the atom?a. a small, positively charged nucleus.  b. electrons in planetary-like orbits. c. quantized energy levels.  d. an electron probability cloud.

15. 15. A hydrogen atom is in the ground state when its electrona. is in the middle of the atom.  b. has been completely ionized.c. in the innermost orbit.  d. has absorbed a photon.

16.According to the Pauli exclusion principle,a. no two electrons can have the same set of values for the four quantum numbers.b. electrons are excluded from entering the nucleus.c. electrons must exist in discrete energy states.d. electrons cannot be removed from an atom.

17. 17. The number of electrons that can be accommodated in an l = 6 subshell is a. 6  b. 12   c. 13   d. 26

 
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