Lecture 5.1- Atomic Orbitals

Section 5.1 Lecture for Honors & Prep Chemistry

1. BELLWORK- Lithium-7 drawing
Draw a picture that represents the
structure of a Lithium-7 atom.

2. BELLWORK- Lithium-7 drawing
Draw a picture that represents the
structure of a Lithium-7 atom.

3. The timeline shoes the development
of atomic models from 1803 to 1911.
5.1

4. Bohr proposed that an electron is
found only in specific circular paths,
or orbits, around the nucleus.
Each orbit has a fixed amount
of energy and is called an
energy level.

6. A quantum of energy is the
amount of energy required to
move an electron from one energy
level to another energy level.

7. 5.1

8. Like the rungs of the
strange ladder, the
energy levels in an
atom are not equally
spaced.
5.1

9. Like the rungs of the
strange ladder, the
energy levels in an
atom are not equally
spaced.
The higher the energy
level occupied by an
electron, the less
energy it takes to
move from that energy
level to the next higher
energy level.
5.1

10. The timeline shows the development
of atomic models from 1913 to 1932.
5.1

11. The quantum mechanical model
determines the energy level of
each electron and defines an
area where each electron is
probably located.
5.1

12. 5.1

13. Austrian physicist Erwin Schrödinger
(1887–1961) used new theoretical
calculations and results to devise and
solve a mathematical equation describing
the behavior of the electron in a hydrogen
atom.
5.1

14. Austrian physicist Erwin Schrödinger
(1887–1961) used new theoretical
calculations and results to devise and
solve a mathematical equation describing
the behavior of the electron in a hydrogen
atom.
The modern description of the electrons
in atoms, the quantum mechanical model,
comes from the mathematical solutions to
the Schrödinger equation.
5.1

15. The propeller blade has the same
probability of being anywhere in the blurry
region, but you cannot tell its location at
any instant.
The electron cloud of an atom can be
compared to a spinning airplane propeller.

16. In the quantum mechanical model, the
probability of finding an electron within a
certain volume of space surrounding the
nucleus can be represented as a fuzzy cloud.
The electron cloud is more dense
where the probability of finding the
electron is high.

18. The boundary of
an atom is
defined as the
volume that
encloses a 90%
probability of
containing its
electrons.

19. The electron cloud is divided into
energy levels. (distance from
nucleus)
Energy levels are divided into energy
sublevels. (shape of electron cloud)
Energy sublevels contain atomic
orbitals. (probable location for 2 e
-
)

20. 5.1

21. An atomic orbital is an area where
there is a high probability of finding
1 or 2 electrons.
Each sublevel (s,p,d or f)
contains orbitals of a specific
shape.
5.1

22. The s orbitals are spherical, and p orbitals
are dumbbell-shaped.
5.1

23. Four of the five d orbitals have the same
shape but different orientations in space.
5.1

24. s sphere 1 per energy level
p “peanut” 3 per energy level
d “daisy” 5 per energy level
f “freaky!” 7 per energy level

25. Observe the characteristics of atomic orbitals.

26. Observe the characteristics of atomic orbitals.

27. Higher energy levels contain larger
orbitals with more energetic
electrons in them.

28. The number of electrons allowed in
each of the first four energy levels are
shown here.
5.1

29. Energy
level
energy sublevels Max #
of e
-
11s 1 orbital2
22s 2px3 4 orbitals8
33s 3px3 3dx5 9 orb.18
44s 4px3 4dx5 4fx7
16 orbitals!
32

30. elementAtomic number# of electrons
Oxygen 8 8
Sulfur 16 16
Seleniu
m
34 34

31. IN SUMMARY

32. IN SUMMARY
Neils Bohr knew that electrons occupy FIXED
energy levels, but he thought electrons orbit
the nucleus on fixed paths like planets orbit
the sun.

33. IN SUMMARY
Neils Bohr knew that electrons occupy FIXED
energy levels, but he thought electrons orbit
the nucleus on fixed paths like planets orbit
the sun.
Schrodinger, deBroglie, and Einstein were
major contributers to our current
understanding of atomic structure.

34. IN SUMMARY
Neils Bohr knew that electrons occupy FIXED
energy levels, but he thought electrons orbit
the nucleus on fixed paths like planets orbit
the sun.
Schrodinger, deBroglie, and Einstein were
major contributers to our current
understanding of atomic structure.
Electrons can be found in certain regions
called atomic ORBITALS, which are the
mathematical solutions to complex equations
of probability.

35. IN SUMMARY
Neils Bohr knew that electrons occupy FIXED
energy levels, but he thought electrons orbit
the nucleus on fixed paths like planets orbit
the sun.
Schrodinger, deBroglie, and Einstein were
major contributers to our current
understanding of atomic structure.
Electrons can be found in certain regions
called atomic ORBITALS, which are the
mathematical solutions to complex equations
of probability.
An atomic orbital is an area where an electron
can be found.

36. 1. Rutherford's planetary model of the atom
could not explain
a.The results of his gold foil experiment.
b.the chemical properties of elements.
c.the distribution of mass in an atom.
d.the distribution of positive and negative
charges in an atom.
5.1 Section Quiz.

37. 1. Rutherford's planetary model of the atom
could not explain
a.The results of his gold foil experiment.
b.the chemical properties of elements.
c.the distribution of mass in an atom.
d.the distribution of positive and negative
charges in an atom.
5.1 Section Quiz.

38. 2. Bohr's model of the atom proposed that
electrons are found
a.embedded in a sphere of positive charge.
b.in fixed positions surrounding the
nucleus.
c.in circular orbits at fixed distances from the
nucleus.
d.orbiting the nucleus in a single fixed
circular path.
5.1 Section Quiz.

39. 2. Bohr's model of the atom proposed that
electrons are found
a.embedded in a sphere of positive charge.
b.in fixed positions surrounding the
nucleus.
c.in circular orbits at fixed distances from the
nucleus.
d.orbiting the nucleus in a single fixed
circular path.
5.1 Section Quiz.

40. 3. What is the lowest-numbered principal energy
level in which p orbitals are found?
a.1
b.2
c.3
d.4
5.1 Section Quiz.

41. 3. What is the lowest-numbered principal energy
level in which p orbitals are found?
a.1
b.2
c.3
d.4
5.1 Section Quiz.