6 Quarks

1
MODERN PHYSICS V
6 Quarks 6 leptons (electron, 3 neutrinos, two
others) Hadrons Baryons (3 quarks) and Mesons
(2) Plus their antiparticles Four Fundamental
forces Strong Force (gluons) Weak force (weird
particles) Electromagnetic force
(photons) Gravity (gravitons) - They
both have mass - They have opposite sign - If
they meet, they self-annihilate and release energy
2
The Energy Levels of the Hydrogen Atom (The Well)

• In order for an electron to change from a lower
  energy state to a higher energy state, the
  incident photon must have the exact amount of
  energy equivalent to the difference in energy
  levels of the hydrogen atom.
• Ephoton Ei Ef
• For example an electron transitioning from the
  ground state (n1) to a higher energy level (n2)
  requires a photon of 10.2eV.
• If the photon had only 10eV of energy or 10.5eV
  of energy, nothing would happen!

3
Quantization of the Energy Levels of the Hydrogen
Atom

• Ephoton Ei Ef
• While an electron in a hydrogen atom transitions
  from n1 to n3 it needs a photon with exactly
  12.09eV (13.60eV 1.51eV) of energy, how will it
  return to the ground state?
• When transitioning back to the ground state, the
  electron can take one of 3 possible transitions
  3 1, or 3 2 followed by 2 1.
• Each jump would emit a photon with an amount of
  energy equal to the difference between the two
  energy levels.

4
The Energy Levels of the Hydrogen Atom
Excited level Excited level Excited level Excited level Excited level Excited level Excited level Excited level Excited level
n En 2 3 4 5 6 7 8 9 10
1 -13.6 10.2 12.09 12.75 13.06 13.22 13.32 13.39 13.43 13.46
2 -3.4   1.889 2.55 2.856 3.022 3.122 3.188 3.232 3.264
3 -1.51     0.661 0.967 1.133 1.234 1.299 1.343 1.375
4 -0.85       0.306 0.472 0.572 0.638 0.682 0.714
5 -0.54         0.166 0.266 0.332 0.376 0.408
6 -0.38           0.1 0.165 0.21 0.242
7 -0.28     eV       0.065 0.11 0.142
8 -0.21               0.045 0.077
9 -0.17                 0.032
10 -0.14                  
En (-13.6 eV)Z2/n2
5
The Energy Levels of the Hydrogen Atom
n En 2 3 4 5 6 7 8 9 10
1 1.6E-18 1.9E-18 2.0E-18 2.1E-18 2.1E-18 2.1E-18 2.1E-18 2.1E-18 2.2E-18
2 -5.4E-19   3.0E-19 4.1E-19 4.6E-19 4.8E-19 5.0E-19 5.1E-19 5.2E-19 5.2E-19
3 -2.4E-19     1.1E-19 1.5E-19 2.0E-19 2.1E-19 2.1E-19 2.2E-19
4 -1.4E-19       4.9E-20 7.6E-20 9.2E-20 1.1E-19 1.1E-19
5 -8.7E-20         2.7E-20 4.3E-20 5.3E-20 6.0E-20 6.5E-20
6 -6.0E-20           1.6E-20 2.6E-20 3.4E-20 3.9E-20
7 -4.4E-20     Joules       1.0E-20 1.8E-20 2.3E-20
8 -3.4E-20               7.1E-21 1.2E-20
9 -2.7E-20                 5.1E-21
10 -2.2E-20                  
En (-2.18 x 10-18 J)Z2/n2
6
The Energy Levels of the Hydrogen Atom
n 2 3 4 5 6 7 8 9 10
1 2.5E15 2.9E15 3.1E15 3.2E15 3.2E15 3.2E15 3.2E15 3.3E15
2   4.6E14 6.9E14 7.3E14 7.6E14 7.7E14 7.8E14 7.9E14
3     1.6E14 2.3E14 2.7E14 3.0E14 3.1E14 3.3E14 3.3E14
4       7.4E13 1.1E14 1.4E14 1.5E14 1.7E14 1.7E14
5         4.0E13 6.5E13 8.0E13 9.1E13 9.9E13
6           2.4E13 4.0E13 5.1E13 5.9E13
7   Frequency in Hz Frequency in Hz Frequency in Hz     1.6E13 2.7E13 3.4E13
8               1.1E13 1.9E13
9                
E hf
7
The Energy Levels of the Hydrogen Atom
n 2 3 4 5 6 7 8 9 10
1
2  
3    
4      
5        
6          
7     Light      
8              
9                
8
(No Transcript)
9
Key Ideas

• The atom is defined as a probability cloud of
  electrons with a centrally located nucleus.
• The nucleus is fractionally smaller compared to
  the entire atom (1/100,000th).
• J.J. Thompson developed the first working model
  of the atom the plum-pudding model.
• Earnest Rutherford developed the
  nuclear/planetary model of the atom as a result
  of the gold foil experiment.
• Neils Bohr further developed the planetary model
  of the atom and solved many questions about the
  hydrogen atom.

10
Covered Standards Mon 5/7 5.3f Among other
things, mass-energy and charge are conserved at
all levels (from subnuclear to cosmic). 5.3g
The Standard Model of Particle Physics has
evolved from previous attempts to explain the
nature of the atom and states that atomic
particles are composed of subnuclear particles
the nucleus is a comglomeration of quarks which
manifest themselves as protons and neutrons
each elementary particle has a corresponding
antiparticle Stress Tues 5/8 5.3b Charge is
quantized on two levels. On the atomic level,
charge is restricted to multiples of the
elementary charge (charge on the electron or
proton). On the subnuclear level, charge appears
as fractional values of the elementary charge
(quarks). 5.3j The fundamental source of all
energy in the universe is the conversion of mass
into energy.
11
Covered Standards Wed 5/9 5.3j The
fundamental source of all energy in the universe
is the conversion of mass into energy. 5.3a
States of matter and energy are restricted to
discrete values (quantized). 5.3c On the atomic
level, energy is emitted or absorbed in discrete
packets called photons. 5.3 Compare energy
relationships within an atoms nucleus to those
outside the nucleus. i. interpret energy-level
diagrams ii. correlate spectral lines with an
energy-level diagram
12
observe and explain energy conversions in
real-world situations recognize and describe
conversions among different forms of energy in
real or hypothetical devices such as a motor, a
generator, a photocell, a battery 4.1b Energy may
be converted among mechanical, electromagnetic,
nuclear, and thermal forms.
13
4.3a An oscillating system produces waves. The
nature of the system determines the type of wave
produced. 4.3d Mechanical waves require a
material medium through which to travel. 4.3g
Electromagnetic radiation exhibits wave
characteristics. Electromagnetic waves can
propagate through a vacuum. 4.3l Diffraction
occurs when waves pass by obstacles or through
openings. The wavelength of the incident wave and
the size of the obstacle or opening affect how
the wave spreads out. 4.3 Explain variations in
wavelength and frequency in terms of the source
of the vibrations that produce them, e.g.,
molecules, electrons, and nuclear particles. iv.
differentiate between transverse and longitudinal
waves
14
5.3h Behaviors and characteristics of matter,
from the microscopic to the cosmic levels, are
manifestations of its atomic structure. The
macroscopic characteristics of matter, such as
electrical and optical properties, are the result
of microscopic interactions. 5.3i The total of
the fundamental interactions is responsible for
the appearance and behavior of the objects in the
universe.
15
5.3d The energy of a photon is proportional to
its frequency. 5.3e On the atomic level, energy
and matter exhibit the characteristics of both
waves and particles.