| 5.1 |
Models
Help Us Visualize the Invisible World of Atoms |
| 5.1a |
Conceptual and Physical Models |
Summary:
Physical models replicate an object on a different scale, while
conceptual models describes the behavior of a system. How these
models apply to atoms is discussed. |
Duration:
7:52. |
| 5.1b |
Graphic Depictions Of Atoms |
Summary:
Graphic depictions based on conceptual models represent how
atoms behave, not what they look like. Several graphical representations
of atoms are shown and briefly discussed. |
Duration:
4:11 |
| 5.2 |
Light Is a Form of Energy |
| 5.2a |
Electromagnetic
Radiation |
Summary:
There is a very close relationship between electricity and magnetism.
They may regenerate each other to give rise to electromagnetic
radiation. |
Duration:
6:21 |
| 5.2b |
The Electromagnetic
Spectrum |
Summary:
The electromagnetic spectrum includes everything from radio
waves to gamma waves, including a region known as visible light.
|
Duration:
7:25 |
| 5.2c |
What Is
White, What is Black? |
Summary:
Using a prism, a sheet of diffraction grating plastic or a spectroscope,
white light can be broken into its separate components. |
Duration:
5:32 |
| 5.3 |
Atoms
Can Be Identified by the Light They Emit |
| 5.3a |
Elemental
Fingerprints |
Summary:
When atoms of an element are heated to a point where they emit
light, it is found that they only emit characteristic frequencies
of color. Demonstrations of H, He, and Ne are shown. |
Duration:
5:37 |
| 5.3b |
Encore
Presentation |
Summary:
Kai and Maile watch a firework display in Waikiki through a
pair of diffraction grating glasses. Elemental spectra can be
seen in the elements used to make the fireworks. |
Duration:
1:31 |
| 5.4 |
Niels
Bohr Used the Quantum Hypothesis to Explain Atomic Spectra |
| 5.4a |
Niels
Bohr's Planetary Model |
Summary:
Something that is said to be quantized simply means that it
is made of a number of fundamental units. Bohr applied the quantum
hypothesis to the structure of the atom to explain atomic spectra. |
Duration:
5:21 |
| 5.4b |
Bohr's
Explanation of Atomic Spectra |
Summary:
Bohr proposed that electrons are restricted to particular orbits
which he designated by principal quantum numbers. When electrons
drop to lower energy levels, they emit light, giving rise to
a specific atomic spectra. |
Duration:
4:56 |
| 5.5 |
Electrons
Exhibit Wave Properties |
| 5.5a |
Wave Mechanics |
Summary:
Particles such as electrons also have wave-like properties.
Properties of waves, or wave mechanics, is discussed. |
Duration:
7:34 |
| 5.5b |
The Formation Of Standing Waves |
Summary:
Standing waves occur when the frequency of the wavelength matches
the dimensions of the container. An understanding of standing
waves helps explain why electrons are restricted to different
orbits. |
Duration: 7:34 |
| 5.5c |
The 3-D Waves Of Electrons |
Summary:
An electron is a 3-dimensional type of wave, which can be represented
by a probability clouds and atomic orbitals. Examples of various
atomic orbitals are discussed. |
Duration:
7:34 |
| 5.5d |
Whistle While You Work |
Summary:
This video is a demonstration of how sound can be quantized
when its wavelength matches the confined region of a tube. |
Duration:
1:10 |
| 5.6 |
Energy-Level
Diagrams Describe How Orbitals Are Occupiedl |
| 5.6a |
Energy-Level Diagrams |
Summary:
There are many atomic orbitals that describe the regions of
space where electrons are found. Energy-level diagrams are used
to describe these orbitals and how they are occupied by electrons.
|
Duration:
7:02 |
| 5.6b |
Elements With Similar Properties |
Summary:
An electron configuration describes the arrangement of electrons
in the orbitals of an atom and also gives rise to its properties.
Elements with similar chemical and physical properties are found
grouped together in the periodic table. |
Duration: 4:15 |
| 5.7 |
Orbitals
of Similar Energies Can Be Grouped into Shells |
| 5.7a |
The Grouping Of Atomic Orbitals |
Summary:
Orbitals of similar energy can be grouped together in atomic
shells. Each shell has a capacity for a certain number of electrons,
based on the energy levels of the orbitals that the shell is
derived from. |
Duration: 7:46 |
| 5.8 |
The
Periodic Table Helps Us Predict Properties of Elements |
| 5.8a |
Periodic Trends |
Summary:
Periodic trends are found with elements that have similar electron
configurations, thus causing the elements to have similar physical
and chemical properties. Graphics of the shell model are used
to explain inner-shell shielding and effective nuclear charge. |
Duration: 6:57 |
| 5.8b |
Atomic Size |
Summary:
Using the concepts of inner shell shielding and effective nuclear
charge, periodic trends such as atomic size are explained. |
Duration: 7:01 |
| 5.8c
|
Ionization
Energy |
Summary: Another periodic trend is ionization energy, which
is the amount of energy required to pull an electron away from
an atom. The greater the effective nuclear charge, the more
energy it will take to pull an electron away. |
Duration: 6:44 |
