Electrons

1

• Chapter 4
• Electrons
• In Atoms

2
Properties of Light

• ___________________ a form of energy that
  exhibits wavelike behavior as it travels through
  space. (ex. Visible light, x-rays, UV, IR,
  radio)
• ____________________ all forms of
  electromagnetic radiation together make up the
  spectrum.
• 4-2

3
Properties of Light
4
Characteristics of Waves

• There are 4 main characteristics of waves
• 1) ___________ The height of the wave measured
  from its origin to its peak. When you
  increase the intensity, or brightness of light,
  you are increasing its amplitude.
• 4-4

5
Characteristics of Waves

• 4-3

6
Characteristics of Waves

• 2)________________ the distance between
  corresponding points on adjacent waves.
  Wavelength is designated by the Greek symbol
  __________.
• Wavelength ___
• 4-6

7
Characteristics of Waves

• 4-5

8
Characteristics of Waves

• 3) ___________ the number of waves that pass a
  given point in a specific time. Measured in
  cycles per second (cycle/second, or s-1) The SI
  unit for this is Hertz. 1.0 Hz 1.0 s-1
• Frequency is designated by the Greek symbol ___.
  Frequency ____
• 4-8

9
Characteristics of Waves
10
Characteristics of Waves

• 4) _________ the speed of light is constant.
  It is rounded to _________ m/s. The speed of
  light is represented by the letter ____.
• ___ ??
• 4-10

11
The Photoelectric Effect

• Refers to the emission of _________ from a metal
  when light shines on the metal.
• __________ the minimum amount of energy that
  can be lost or gained by an atom
• ____________, a German physicist studied quanta
  of light and found
• 4-11

12
The Photoelectric Effect

• E(energy) _____
• Where h is Planks Constant and has a value
  of 6.6262 x 10-34 Js
• 4-12

13
The Photoelectric Effect

• Einstein expanded upon this to propose that light
  has a ______________, acting as a _______ under
  some circumstances and a ____________ under
  others.
• __________ a particle of electromagnetic
  radiation having zero mass and carrying a quantum
  of energy.
• 4-13

14
Line Emission Spectrum

• ______________ the lowest energy state of an
  atom
• _____________ a state in which an atom has a
  higher potential energy than it has in its
  ground state.
• 4-14

15
Line Emission Spectrum

• _____________________ a graph that indicates
  the degree to which a substance emits radiant
  energy with respect to ______________.
• ______________________ the emission of a
  continuous range of frequencies of
  electromagnetic radiation.
• 4-15

16
H Emission Spectrum

• _____________ a Danish physicist who proposed a
  hydrogen-atom model that linked the atoms
  electron to photon emission. (electrons circle
  the nucleus in _______)
• 4-16

17
H Emission Spectrum

• Emission Line Spectrum a graph that indicates
  the degree to which a substance emits radiant
  energy with respect to wavelenth.
• Continuous Spectrum the emission of a
  continuous range of frequencies of
  electromagnetic radiation.
• 4-17

18
H Emission Spectrum

• Emission Line Spectrum a graph that indicates
  the degree to which a substance emits radiant
  energy with respect to wavelenth.
• Continuous Spectrum the emission of a
  continuous range of frequencies of
  electromagnetic radiation.
• 4-18

19
The Quantum Model

• ____________________________ states that it is
  impossible to determine simultaneously both the
  ___________ and _______________ of an electron or
  any other particle.
• ___________________ describes mathematically
  the wave properties of electrons and other very
  small particles.
• 4-19

20
The Quantum Model

• ______________________ specify the properties of
  atomic orbitals and the properties of electrons
  in orbitals.
• Quantum numbers were developed based on the
  ____________________, developed by Austrian
  physicist Erwin Shrödenger.
• 4-20

21
The Quantum Model

• __________________________ indicates the main
  energy level occupied by the electron. Values
  are positive integers only (1, 2, 3, 4 with 1
  being the lowest energy level closest to the
  nucleus) _______________________ indicates the
  shape of the orbital. Values are 0, 1n-1)
• 4-21

22
The Quantum Model

• l 0 s l 1 p l 2 d l 3 f
• l 0 S l 1 p l 2
  d l 3 f
• 4-21

23
The Quantum Model

• Magnetic Quantum Number (m) indicates the
  orientation of an orbital around the nucleus.
  Values, including zero, are l to l
• l 0 s orbital has only one orientation
  (sphere)
• l 1 p has three orientations
• l 2 d has five orientations
• l 3 f has seven orientations
• 4-23

24
The Quantum Model
25
The Quantum Model
26
The Quantum Model
27
The Quantum Model

• ________________________ indicates the two
  fundamental spin states of an electron in an
  orbital. Values are 1/2 or -1/2.
• ______________________ the arrangement of
  electrons in an atom.
• 4-27

28
Orbital Filling Diagrams

• There are ____________, named after the
  scientists that discovered them, that govern the
  filling of these orbitals with electrons
• The ________________ an electrons occupies the
  lowest energy orbital that can receive it.
• 4-28

29
Orbital Filling Diagrams

• 2) The ________________________ no two
  electrons in the atom can have the same set of
  four quantum numbers.
• 3) _______________ Electrons occupy equal
  energy orbitals so that a maximum numbered of
  unpaired electrons results, and all e- in singly
  occupied orbitals must have the same spin.
• 4-29

30
Orbital Filling Diagrams

• When using this form, each electron is designated
  as an _______ ________ pointing up or down to
  show opposite spins. Each orbital is designated
  with a labeled line ____ or __ __ __
• 1s 2p
• ____________lines show multiple orbitals (1 for
  s, 3 for p, 5 for d)
• 4-30

31
Orbital Filling Diagrams

• Orbitals fill going _____________ each period
  (_____) on the periodic table, from the lowest
  energy level up. (Aufbau). Dont forget, when
  they pair, they have ____________ (Pauli), but
  they wont pair until each available orbital has
  an unpaired electron in it first (Hund)
• 4-31

32
Orbital Filling Diagrams

• 4-32
• 4-31

33
Orbital Filling Diagrams

• _____________, with one electron, would have an
  orbital filling diagram of
• ?
• 1s
• __________, with 2 electrons, would be
• ??
• 1s
• Now your at the end of the first period, start
  again in the 2nd period with 2s
• 4-33

34
Orbital Filling Diagrams

• Lithium
• ?? ?
• 1s 2s
• Be
• ?? ??
• 1s 2s
• B
• ?? ?? ? _ _
• 1s 2s 2p

35
Orbital Filling Diagrams

• Which of these would be correct for oxygen (with
  8 e-)
• O
• ?? ?? ?? ? ??
• 1s 2s 2p
• OR
• ?? ?? ?? ? ?
• 1s 2s 2p
• ____________ is correct, the _________ example
  violates the Pauli Exclusion Principle.
• 4-35

36
Practice

• Write the orbital filling notation for the
  following elements
• Be_________________________
• F__________________________
• Ar_________________________
• Cu_________________________
• 4-36

37
Electron Configurations

• Now your ready to write electron configurations.
  These are simply the orbital diagrams written out
  with superscripts
• Lithium
• ?? ?
• 1s 2s would be written out as 1s2 2s1
• Be
• ?? ??
• 1s 2s would be written out as 1s2 2s2
• B
• ?? ?? ? _ _
• 1s 2s 2p would be written out as 1s22s22p1
• 4-37

38
Practice

• Write the electron configuration for the
  following elements
• Mg________________________
• N_________________________
• Cr________________________
• Cl________________________
• 4-38

39
Electron Configurations

• ___________________ refers to an outer main
  energy level occupied by eight e-
• Once a __________ is complete at the end of a
  period, you can write subsequent configurations
  as having the _______ of the ___________ with the
  additional ___________ electrons.
• Sodium Na would have a noble gas notation of
• ?Ne?3s1
• 4-39

40
Practice

• Write the noble gas notation for the following
  elements
• Na_________________________
• Sb_________________________
• Y__________________________
• F__________________________
• 4-40

41

• Ch. 4
• The
• End
• 4-41