Transcript Ch29-31-2015-Px

AP
FIZZIX
Ch 29-31 PPT Lesson
Thingee
Atomic & Nucular “Theory”
© 2015 D Taylor
Schedule Remaining
•
•
•
•
Atomic/Nucular (Ch 29 - 31)
3 wks on learning “PHYSICS”
6 wks on AP PHAKETS.
Srs on Internship
– Exit Exam (Final X) by ~5/22
• Exempt if taking Nat’l Exam
• OPTIONAL
– Bye Bye
Intro Stuff – Ch29
• Elements
–90 Naturally occurring. Y?
–H was the 1st (14BYA)
–“Rest” formed in stars
•>Fe in supernovae
–Basic building blocks of
matter…
Intro Stuff
• Electron
–Sorta discovered by Volta
and Franklin
• Although Ben never flew the
kite!
–JJ Thompson 1887
• Plum pudding
Overall Atomic History
• ~400 BC: Democritus
– “By convention bitter, by convention sweet, but in
reality atoms and void.“
– Druggee; used opium leaf
• 1704 AD: Uncle Newton
– Proposed a mechanical universe with small
solid masses in motion.
• Wood is wood parts…
• Water is water parts…
Overall Atomic History
• 1803 AD: John Dalton
– Matter is composed of tiny indivisible
particles called atoms.
– All atoms of the one element are identical
but are different from the atoms of other
elements.
– Chemical reactions consist of rearranging
atoms in simple whole number ratios.
Overall Atomic History
• 1859 J. Plucker
– Built the first CRT gas discharge tubes
("cathode ray tube").
• 1869Dmitri Mendeleev
– Arranged elements into 7 groups with similar
properties. He discovered that the properties
of elements "were periodic functions of the
their atomic weights". This became known
as the Periodic Law.
Overall Atomic History
• 1894 G.J. Stoney
–Proposed that electricity was made of
discrete negative particles he
called electrons .
Overall Atomic History
• 1896: JJ Thomson
–Nobel 1906
• Cathode Rays
–Calculated q/m (1.76 x 1011)
–Identified “small negative bodies”
–He called them “corpuscles”
Overall Atomic History
• 1903 Nagaoka
–Postulated a "Saturnian" model of the
atom with flat rings of electrons
revolving around a positively charged
particle.
+
-
Overall Atomic History
• 1905 Albert Einstein (3/14/1879 : Day)
–The “Wonder Year” (Annus Mirabilis papers)
–Published 4 papers that turned science
on it’s proverbial head…
• Photoelectric Effect: Quantized light
• Brownian Motion : Explained molecular
motion & EXISTENCE of atoms
• Special Relativity : ‘c’ is fixed
• Mass/Energy Equivalency: the famous
equation E=mc2
Overall Atomic History
• 1909: James Millikan
–Nobel 1923
–Oil Drop Experiment
• Found charge, thereby the mass of
electron
• Details later
Overall Atomic History
• 1911: Ernest Rutherford
• Proposed a nuclear model of the atom in
which:
– a very small positively charged nucleus
containing most of the mass of the atom
– a very large volume around the nucleus in
which electrons move
– a nucleus containing positively charged protons
– number of protons equal to the number of
electrons
• NAMED  &  nuclear radiations
Overall Atomic History
• 1911: Ernest Rutherford
– Postulated the existence of a neutral
particle in the nucleus to make up for the
calculated mass deficiency in the atoms
studied.
• 1914 H.G.J. Moseley
– Using x-ray tubes, determined the charges on the
nuclei of most atoms. He wrote "The atomic
number of an element is equal to the number of
protons in the nucleus". This work was used to
reorganize the periodic table based upon atomic
number instead of atomic mass.
Overall Atomic History
• 1913: Niels Bohr (Nobel 1922)
• Proposed a 'planetary' model for the
hydrogen atom:
– Electrons move around the nucleus in fixed orbits (like
planets around the sun). An electron in a particular orbit
has constant energy.
– An electron can absorb energy and move to a higher
energy orbit of larger radius. (excited electrons)
– An excited electron can fall back to its original orbit by
emitting energy as radiation.
– Electrons can only exist in certain discrete
energy levels.
Overall Atomic History
• 1927 Heisenberg (Nobel 1932)
– Described atoms by means of
formula connected to the frequencies
of spectral lines. Proposed Principle
of Indeterminancy - you can not know
both the position and velocity of a
particle.
• 1932: James Chadwick
– Found Rutherford’s proposed Neutron.
Overall Atomic History
• ~400 BC: Democritus
• 1803 AD: John Dalton
Mendeleev’s 1st PD
Mendeleev - 1871
Mendeleev - 1871
http://www.chemheritage.org/discover/media/magazine/articles/28-3-setting-the-table.aspx
Thomson PP Model - 1898
Intro Stuff
• John Millikan - 1909
–Oil drop experiment. Nobel ‘23
•Webpage DEMO
F  0
FE  Fg
Eq  mg
PHET Simulation
Intro Stuff
• John Millikan
Intro Stuff
• John Rutherford
Scattering - 1911
•Webpage
Intro Stuff
• John ‘Neils’ Bohr - 1913
– Planetary
model
• Dense nucleus
–P & N
• Orbiting electrons
Bohr (Neils) Model
• “Planetary” model
–Each ‘quantum’ represents a
new ‘orbit’
–Nucleus at the center
–However,…
IT. IS. WRONG.
Problem w/Bohr Model…
Bohr Model
• Bohr’s model was able to
– Account for observed spectral lines
– Calculate the radius of H atoms
• DID NOT account for
– Atoms other than H!
– Why energy was quantized!
• His idea of electrons moving in fixed
orbits like planets was quickly
abandoned, but still taught 102 yr
later.
Chadwick Neutrons - 1932
• Nobel 1935
Heavy N Nucleusii
“Mysterious Radiation”
Thought to be  before.
Neutral – No B Deflection
But, NO PHOTOELECTRIC EFFECT
DeBroglie Theory - 1924
• Nobel 1929
• Suggested electrons have
wave properties, might even
be waves.
–Represented by a standing wave
–DEMO
–Therefore, each e- path must be a
whole (integral) number of ’s
deBroglie Explanation of
Bohr Atomic Model - LINK
Section 27-13
DeBroglie Theory - 1924
• Wavelengths of all particles
are
h

mv
•  = wavelength
• h = Planck’s Constant
• m = mass (kg)
• v = velocity (m/s)
DeBroglie Theory - 1924
• Calculate  of H
e
h

mv

6.6 x10
9.1x10
 3.3x10
31
10
34
kg  m

2
s
kg 2.2 x10 m
m
6
s
Schroedinger’s Theory - 1932
• Nobel 1933 w/Dirac
• Fully described motion, energy, and
placement of electrons in one
equation.
–MUCH too difficult to show you without
having your head explode…
–So here it is…
Intro Stuff
• Line Spectra
–LINK THINGEE
• Thru X-Rays
IR?
UV?
Spectral Lines
Red Shift?
Visible Light =
400-700 nm
820-1875 nm
91-122 nm
IR
UV
365-656 nm
3000-4000 nm
Visible
Radio
Ch27 Specifics
Planck’s Blackbody Radiation
T
3
2.90 x10 mK
 peak
Planck’s Blackbody Radiation
Wein’s Law
• Surface Temp of Sun
T
3
2.90 x10 mK
 peak
3
2.90 x10 mK

9
500 x10 m
 6000 K
Planck’s Blackbody Radiation
Wein’s Law
3
2.90 x10 mK
• Surface Temp of Sirius
T
300nm
T  10,000 K
Planck’s Quantum Hypothesis
E  hf
h  6.626 x10
 4.14 x10
34
15
J s
eV  s
Photoelectric Effect
Photoelectric Effect
• Discovered by Heinrich Hertz in
1897 (Nobel 1925)
– Originally called “Hertz Effect”
• In 1899, J. J. Thomson investigated
ultraviolet light. Thomson deduced
that cathode rays consisted of
negatively charged particles, later
called electrons, which he called
"corpuscles".
Photoelectric Effect
• The answer was finally
provided in 1905 by Albert
Einstein (who else?) who
suggested that light, at least
sometimes, should be
considered to be composed of
small bundles of energy or
particles called photons.
Photoelectric Effect
• Einstein (‘05) theorized that the energy
in each quantum (photon) of light was
equal to the frequency of the light
multiplied by a constant, h, later called
Planck's (Nobel 1918) constant.
• 1915 : Millikan showed that Einstein's
prediction was correct.
– 10 years AFTER Big Al showed the math and
predicted existence of photons.
• Al: Nobel 1921
Photoelectric Effect
KEMax  hf o  Wo
 hf o  
For you, Ross!
Phet Sim…
PhotoElectric Example?
• What is the speed of an ejected electron
from a Na surface of  = 2.28 eV when
illuminated by  = 410 nm?
KEMax  hf o  Wo
1 2
c
mv  h  Wo
2

 c

2 h  Wo 



v
m


3 x108 m / s
15
2 4.14 x10 eVs
 2.28eV 
410nm



9.11x10 31 kg
 5.1x105 m
s
E, m, & P of photons
• Relativity? Yep.
• Rest mass:
m0
• Energy:
KE  hf
• Momentum:
???
P 2
E  mc  c  Pc
v
E hf h
P 

c
c 
2
Photon P: EX 27-6
• 1019 photons emitted per second from 100W
light bulb are all shot at a black piece of paper
and absorbed. Find the Pper-photon and Ftotal.
34
6.63 x10 J  s
 27 kg  m
P 
 1.3 x10
s

500nm
h
N
P
19
1 
 27 kg  m


F

 10 sec 1.3 x10
s

t
t
8
F  10 N
h


Photon Interaction / Pair Production
• PhotoEffect: photon knocks e- out of atom
and photon disappears.
• Photon knocks e- into higher state and photon
disappears.
• **Photon scatters from e- giving some E to eand photon loses E. (Compton Scattering)
• Pair Production: Photon actually creates
matter.
Honors / AP
FIZZIX
Ch H24/AP30 PPT
Lesson Thingee
Nuclear FIZZIX
Intro Stuff
• THE Nucleus
–Why are they there?
Nuclear STRONG Force!
Intro Stuff
• Nuclear Radiation
–Alpha, 
4
He2
Intro Stuff
• Nuclear Radiation
–Beta, 
e

Intro Stuff
• Nuclear Radiation
–Gamma, 
Photon
Not-So-Intro Stuff
•
decay & release of
Energy:
–
(electron) is NOT in
the parent nucleus
and is NOT an orbital
e!
Not-So-Intro Stuff
•
decay
o
+
–N P
–HUH?
+
e
Particles:
• Quarks (1967; Murray Gell Mann)
– Charges of -1/3 or +2/3
– Makes Hadrons [nucleons best
known]
– Nucleons (Fermionic Hadrons)
• 3 Quarks each
• Proton = uud
– u has +2/3, d has -1/3
• Neutron = udd
 Energy
release
234
234
0
Th

Pa

e
90
91
1
 Energy
release
234 .04359 u  234 .04330 u
234 .04359  234 .04330  0.00029
1u  931 .5MeV
E  0.27 MeV
Y?
1u  1.66 x10

E  mc
E  1.66054 x10
 27
27
kg
2


8 2
kg 2.9979 x10
10
E  1.49449 x10 J eV
19
1.6022 x10 J
8
E  9.315 x10 eV

1u  931.5MeV

EX 30-3 pg 838
• Find mass defect of He nucleus
4
2
He  2mn  2mH
 2(1.008665u )  2(1.007825u )
 4.032980
EX 30-3 pg 838
• Find mass defect of He nucleus
4
2
He  2mn  2mH
 2(1.008665u )  2(1.007825u )
 4.032980
• However…
mHe  4.002603u
EX 30-3 pg 838
• Missing mass?
4.032980u  4.002603u  0.030377u
0.030377u  931.5 MeV u  28.3MeV


• Where is it? What happened to it? What the
WHAT?
– Energy: KE or radiation
– Called Binding Energy (Energy needed to break
the nucleus apart.)
EX 30-6 pg 843
• Disintegration Energy of UTh?
U
228
90
U
228
90
232
92
232
92
Th ?
Th  He
4
2
U  232.037146u
232
92
Th  228.028731u
228
90
4
2
He  4.002603u
EX 30-6 pg 843
Th  He  228
.028731
u  4.002603u
Energy
of UTh?
228
4
• 90Disintegration
2
 232.031334u
U  232.037146u
232
92
m  232.037146u  232.031334u
 0.005812u
E  0.005812u  931.5 MeV
u
 5.4 MeV


Intro Stuff
• Nuclear Radiation
–Human exposure
Natural
Medical
Weapons
Nuke Plants
Knotes
EXAM #7 THIS WEEK
B & Atomic/Nuclear Intro Shtuff
 MG: Tuesday
 SA: FRIDAY!
Background radiation:
24+27+28+40+200 =
319 mrem = 3.19 mSv
= 3180 Sv
Doses
• The following is a graphical
representation of human radiation
absorption.
• Just in case the numbers are
confusing…
• Based on radiation data provided by the
lead nuclear reactor operator at Reed
College, Oregon
– http://reactor.reed.edu/
http://xkcd.com/radiation/
http://xkcd.com/radiation/
Note: FOR A YEAR!!!
http://xkcd.com/radiation/
Note: 36.5 Sv FOR A YEAR!!!
http://xkcd.com/radiation/
Note: A COAL PLANT!!!
http://xkcd.com/radiation/
http://xkcd.com/radiation/
http://xkcd.com/radiation/
http://xkcd.com/radiation/
http://xkcd.com/radiation/
http://xkcd.com/radiation/
Doses (Wiki: Sieverts)
• 0 – 0.25 Sv (0 - 250 mSv): None
• 0.25 – 1 Sv (250 - 1000 mSv): Some people feel nausea
and loss of appetite; bone marrow, lymph nodes, spleen
damaged.
• 1 – 3 Sv (1000 - 3000 mSv): Mild to severe nausea, loss
of appetite, infection; more severe bone marrow, lymph
node, spleen damage; recovery probable, not assured.
• 3 – 6 Sv (3000 - 6000 mSv): Severe nausea, loss of
appetite; hemorrhaging, infection, diarrhea, skin peels,
sterility; death if untreated.
• 6 – 10 Sv (6000 - 10000 mSv): Above symptoms plus
central nervous system impairment; death expected.
• Above 10 Sv (10000 mSv): Incapacitation and death.
Intro Stuff
• Half Life
–Time it takes for ½ of
radioactive material to
“disappear”.
N  Noe
 t
 N 
  t
ln 

N
 o
AP B:
Don’t need
this math…
T1 
2
ln 2


0.693

AP B:
Don’t need
this math…
And finally….
E  mc
2
Derivation of
2
E=mc
Yum-Yum Physics!
E=mc2 meaning?
• Energy/Matter EQUIVALENCY.
• Matter changes to Energy &
Verse Visa
• THEY ARE THE SAME THING!
Strange World of
Sub-Atomic Particles
Thing
Size
Atom
1x10-10m (1 )
“PROTON”
1x10-15m (1 fm)
Quark
< 1x10-19m (1/10,000 th P)
String
< 1x10-35m
Particle Adventure
• Online Atomic/Nuclear tutorial
• Completed as HOMEWORK!
– Keep an eye on EITHER
• DS.com
• Giancoli HW Site
– Specific duedates
– GRADED!
Honors / AP
FIZZIX
Ch 25/30 PPT
Lesson Thingee
Nuclear Energy
Fuels that
Produce Electricity
in the U.S.
Comparison Chart
ONLINE…
Fishin’ or Fooshun?
•Fission
–Splitting of nuclei
•Fusion
–QT Movie
Stuff
Advantage(s)
Disadvantage(s)
COAL
*Inexpensive
*Easy to recover (in U.S.
and Russia)
*Requires expensive air
pollution controls (e.g.
mercury, sulfur dioxide)
*Significant contributor to
acid rain and global
warming
*Requires extensive
transportation system
*Dangerous to mine
(Chile, W VA… 200
deaths per year…)
Stuff
Advantage(s)
Disadvantage(s)
NUCLEAR
(Fission)
*Fuel is inexpensive
*Energy generation is
the most concentrated
source
*Waste is more compact
than any source
*Extensive scientific
basis for the cycle
*Easy to transport as
new fuel
*No greenhouse or acid
rain effects
*Requires larger capital
cost because of
emergency, containment,
radioactive waste and
storage systems
*Requires resolution of
the long-term high level
waste storage issue in
most countries
*Potential nuclear
proliferation issue
Stuff
Advantage(s)
Disadvantage(s)
HYDRO
(Water)
*Very inexpensive once
dam is built
*Government has
invested heavily in
building dams,
particularly in the
Western U.S.
*Very limited source
since depends on water
elevation
*Many dams available
are currently exist (not
much of a future
source[depends on
country])
*Dam collapse usually
leads to loss of life
*Dams have affected fish
(e.g. salmon runs)
*Environmental damage
for areas flooded (backed
up) and downstream
Stuff
Advantage(s)
Disadvantage(s)
WIND
*Wind is free if available.
As it turns out, the US has
many areas available.
*Good source for periodic
water pumping demands of
farms as used earlier in
1900's
*Generation and maintenance
costs have decreased
significantly. Wind is proving
to be a reasonable cost
renewable source.
*Well suited to rural areas.
Examples include MidColumbia areas of Oregon
and Washington, western
Minnesota, Atlantic Ocean off
Cape Cod.
*Need 3x the amount of
installed generation to
meet demand
*Limited to windy areas.
*Limited to small
generator size; need
many towers.
*Highly climate
dependent - wind can
damage equipment
during windstorms or not
turn during still summer
days.
*May affect endangered
birds, however tower
design can reduce
impact..
Stuff
Advantage(s)
Disadvantage(s)
Gas/Oil
*Good distribution
system for current use
levels
*Easy to obtain
(sometimes)
*Better as space heating
energy source
*Very limited availability
as shown by shortages
during winters several
years ago & now
*Considered to be major
contributor to global
warming
*Very expensive for
energy generation
*Large price swings with
supply and demand
*Liquified Natural Gas
storage facilities and gas
transmission systems
have met opposition from
environmentalists.
Stuff
Advantage(s)
Disadvantage(s)
SOLAR
*Sunlight is free when
available
*Costs are dropping.
*Limited to southern
areas of U.S. and other
sunny areas throughout
the world (demand can
be highest when least
available, e.g. winter
solar heating)
*Does require special
materials for
mirrors/panels that can
affect environment
*Current technology
requires large amounts of
land for small amounts of
energy generation
Stuff
Advantage(s)
Disadvantage(s)
BIOMASS
*Industry in its infancy
*Could create jobs
because smaller plants
would be used
*Inefficient if small plants
are used (<10%)
*Considered to be THE
significant contributor to
global warming because
fuel has low heat content
Stuff
Advantage(s)
Disadvantage(s)
Refuse
*Fuel can have low cost
*Could create jobs
because smaller plants
would be used
*Low sulfur dioxide
emissions
*Inefficient if small plants
are used
*Could be significant
contributor to global
warming because fuel
has low heat content
*Flyash contains metals
like mercury, arsenic,
cadmium and lead
*Contain dioxins and
furans in air and ash
releases
Stuff
Advantage(s)
Disadvantage(s)
H
*Combines easily with
*Very costly to produce
oxygen to produce water *Takes more energy to
and energy
produce hydrogen then
energy that could be
recovered.
(NEGATIVE efficiency!)
Stuff
Advantage(s)
Disadvantage(s)
Fusion
*Hydrogen and tritium
could be used as fuel
source
(Plentiful in ocean water)
*Higher energy output
per unit mass than
fission by 106
*Low radiation levels
associated with process
than fission-based
reactors
*Breakeven point has not
been reached after ~40
years of expensive
research and
commercially available
plants not expected for at
least 35 years.
(closest is PPPL, NJ.
98% BE)
Leptons & Taus & Quarks! Oh, MY!
• Types of Quarks
–Up / Down
–Top / Bottom
–Charm / Strange