Author Question: Using the restrictions set forth by the uncertainty principle, which of the following combinations ... (Read 27 times)

Pea0909berry · **on:** Jul 28, 2018

Using the restrictions set forth by the uncertainty principle, which of the following combinations of values is it possible to know simultaneously?

a.I, II, III, IV, V, VI, VII
b.I, III, VI, VII
c. II, III, VI, VII
d. III, IV, VI, VII

Question 2

Bohr found that the total angular momentum of the hydrogen atom was L = n

, but this prediction was incorrect. Choose the statement below that best explains why.
a.The Zeeman effect prevents certain orientations of L.
b.Bohr's semiclassical planetary model of the atom did not include space quantization of angular momentum.
c.Bohr's restrictions allowed for a state where L = 0, while this is quantum mechanically forbidden by the uncertainty principle.
d. Bohr's model allowed the electrons to pass through the nucleus as well as orbiting around it.

abro1885 · **Reply #1 on:** Jul 28, 2018

Answer to Question 1

c.
There is no violation of the uncertainty principle from knowing the magnitude of the total angular momentum, one component, and the angular momentum quantum number and magnetic quantum number. In fact, the total angular momentum depends on the angular momentum quantum number and the z component of the total angular momentum depends on the magnetic quantum number.

Answer to Question 2

b.
Bohr's planetary model with the electrons in orbit around a nucleus was not complete. While the picture of such a well-known classical subject is sometimes useful to describe a complex situation, in this case Bohr's model leaves out the space quantization of the angular momentum. Since the angular momentum provided by the magnetic quantum number is quantized, there are limits to the directions of. This makes the total angular momentum depend on l(l + 1) instead of Bohr's result