Download NSS Physics Curriculum - VII Atomic World Intention Intention Intention

NSS Physics Curriculum - VII Atomic World
Intention
# An extension of the learning of atomic model in
compulsory part and a “feel” of recent
development regarding the tiny atomic world
# Intention of the elective topic
# Line of thought in developing the
elective topic
# Content of the elective topic
# In search of atomic structure
# Limitation in learning and teaching the
elective topic
# The advance of nano science and nano
technology
Science Education Section
Curriculum Development Institute, EDB
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Intention
Intention
# elementary concepts in Quantum
Mechanics, e.g.
# Basic knowledge in nano science, e.g.
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Rutherford’s atomic model
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physical properties of materials of nano size
„
photoelectric effect
„
the work of transmission electron microscope
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line spectrum
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the work of scanning tunnelling microscopes
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Bohr’s atomic model of hydrogen
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recent development in nano technology …
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energy levels
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wave-particle duality…
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Line of Thought
Line of Thought
# A historical approach
# Emphasis on the differences between
macroscopic and microscopic worlds
„
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physics knowledge is evolving and based
on evidence
a new knowledge / model always led by the
breakthrough of a new idea, a new method
of enquiry, a new discovery or advance of
technology
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wave-particle duality against unique nature
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probabilistic against determinate, etc
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Line of Thought
a. Rutherford’s atomic model
# Applications of wave-particle duality and
probabilistic nature of atomic world (in the scale
of 10-9m)
# A brief history of the development of atomic
model from ancient time to present
# A brief understanding of J. J. Thomson’s
“plum-pudding” model of atom
# Simplified working principles of tools to see the
particles, a demonstration of the impact of
advanced technology to scientific discovery
# The discrepancy revealed from the scattering
experiment performed by Geiger and
Marsden (Rutherford’s scattering experiment)
# Impacts on our society: gradually “common” in
our daily life and the potential hazards to our
society and health
# How the results lead a new atomic model
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a. Rutherford’s atomic model
b. Photoelectric effect
# The limitations of Rutherford’s model
# Photoelectric effect and the results, e.g.
„
spectral lines, why certain elements could
emit X-ray and only a few elements
seemed to be unstable
the I-V characteristic curve,
„
threshold frequency and stopping voltage
# Einstein’s interpretation by use of particle
nature of light and photoelectric equation
# Assumptions Einstein made in accounting for
the photoelectric results
# The influence / impact of the
methodology used to study further
structure of atom and the search of
new particles
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b. Photoelectric effect
c. Bohr’s atomic model of hydrogen
# Physical meaning of each parameter in
the photoelectric equation
# The absorption and emission spectra
# Differences between continuous and line
spectra.
# Intensity of light in terms of number of
“photons” at a given frequency
# Why and what the scientists puzzled by
these line spectra observed
# Photoelectric effect as an evidence of
particle nature of light
# The limitation of classical mechanics to
explain the existence of line spectra
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c. Bohr’s atomic model of hydrogen
c. Bohr’s atomic model of hydrogen
# The postulates proposed by Bohr for his
hydrogen model
# Limitations of Bohr’s atomic model
# How and why electron-volt is commonly used
to describe the energy of an electron (or the
atom)
# How some of the postulates lead the quantum
view of the atomic world, e.g. quantisation in
energy (angular momentum)
# Planck’s constant and use of electron-volt
(eV), ionisation and excitation energies
# Mathematical expression of energy level of an
electron and its account for line spectra
# Some applications of the line spectra, such
as to determine the elements included in a
light source
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d. Particles and waves
e. Probing into nano scale
# de Broglie formula λ=h/p
# Different forms (nano particles, fullerenes,
nano tube and nano wire) and physical
properties of nano size materials, carbon as an
example
# Evidences to show electrons demonstrate
properties of wave, e.g. and diffraction
(interference) of a beam of electrons
# Simplified models of TEM and STM, and to
demonstrate how they work
# Elaboration of the role of de Broglie formula
on how it relates the particle and wave
properties of electron (as well as the
macroscopic and microscopic views of our
understanding of matter)
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# Estimation of anode voltage of TEM for a beam
of electrons of a certain amount of momentum
# The advantages of using TEM and STM
instead of optical microscope
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e. Probing into nano scale
e. Probing into nano scale
# Applications of nano materials in our daily life,
with brief explanation of the working principles,
e.g.
# The use of wave properties of electron as
the breakthrough for greater distinction of
two objects (resolution), Rayleigh
criterion Θ= 1.22λ/d
# The use of probability wave of electrons
in STM, another breakthrough to probe
into the atomic world
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impermeability of gas
„
water-repellence
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transparency
# Details and issues regarding the impact to our
environment and body in using nano materials
(potential hazards and safety concerns)
# Way forward of nano science and nano
technology
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Limitations
Similar Curricula Overseas
# Meaning of quantisation of angular
momentum of an electron and activities to
learn the concept
# Differences between probability wave and
matter wave
# Practical activities
# Some sub-topics would be descriptive
instead of analytical
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IB
UK
(GCSE,
GCE AS /
AL
NSW
(HSC)
Alberta
(Science
10 – 12)
Ontario
(Grade
11 – 12)
Mainland
a. Atomic model
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b. Photoelectric
effect
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c. Bohr model
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d. Particles &
waves
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e. Nano scale
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