7.3.1 Atomic Orbital Size

Question 1

Atomic Orbital Size

Answer 1

• The wave-function solutions to Schrödinger’s equation reveal the allowed energies and location probabilities of the electron.
• The 1s solution to Schrödinger’s equation indicates that the highest probability of finding the electron is 0.53 angstroms (Å) from the nucleus

Question 2

note

Answer 2

• The wave-function solutions to Schrödinger’s equation reveal the allowed energies and location probabilities of the electron.
• We cannot know the location of an electron as a consequence of Heisenberg’s uncertainty principle. We can know something about its energy and probability states.
• The 1s solution to Schrödinger’s equation indicates that the highest probability of finding the electron is 0.53 angstroms (Å) from the nucleus.
• At higher energy levels the most likely location for the
  electron is farther from the nucleus. The 2s energy sublevel has its highest probability outside the 1s maximum. It also has a single node, or region with a zero probability of finding the electron.
• In the 3s energy sublevel, the highest probability of finding the electron is beyond the 2s maximum and there are 2 nodes.
• Higher s energy sublevels produce an electron probability density or “electron cloud” of a greater diameter.

Question 3

The quantum mechanical model of the atom gives up trying to specify the location of the electron and instead shows us what?

Answer 3

The probability of finding the electron

Question 4

The Heisenberg uncertainty principle states that it is impossible to simultaneously know which two things about of an electron?

Answer 4

position, momentum

Question 5

The 1s, 2s, and 3s orbital solutions to Schrödinger’s equation for the hydrogen atom use only which portion of the equation?

Answer 5

radial

Question 6

Which of these graphs shows the distance from the hydrogen nucleus where the electron with lowest energy is most likely to be found?

Answer 6

The probability of finding the electron along any radius decreases with distance, but the number of regions where the electron could be increases with distance, so the maximum probability occurs at about 0.5 Å

Question 7

What are the “dips” in the graphs of radial probability distribution for the 2s and 3s states called?

Answer 7

radial nodes

Question 8

Which of the following explains why the Bohr model of the atom ultimately did not work?

Answer 8

It required knowing the position and momentum of an electron.

Question 9

What information does Schrödinger’s equation combine?

Answer 9

kinetic energy, potential energy, and wave properties

Question 10

The Bohr model of a hydrogen atom predicts that the electron of lowest energy orbits at a distance of 0.5 Å from the nucleus. What does the quantum mechanical model predict is the most likely distance to find a 1s electron?

Answer 10

The same distance, 0.5Å.

Question 11

In addition to information about kinetic energy and potential energy of an electron what additional information does the Schrödinger’s equation provide about an electron?

Answer 11

wave properties

Question 12

To which of the following is the Bohr model of an atom similar?

Answer 12

a planet in orbit around a sun