Tuesday 9/6/16
Chapter 14 - the Atom (finally…)
Learning Goals and the Achievement Scale
4, 3, 2, 1, 0 Scoring Scale.
Discuss Learning Goals.
Pass out Periodic Tables.
Nothing warms the soul…
Score 2: The student demonstrates no major errors or omissions regarding the simpler details and processes that
support the learning goal(s).
The student :
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Can state the key theories or experiments associated with Dalton, Rutherford, Thomson and Bohr.
Can compare the relative sizes and charges of the subatomic particles (protons, neutrons and electrons).
Can define the 3 fundamental forces (strong nuclear, weak nuclear and electromagnetic) at play in the atom.
Can define the terms atom, element, ion and isotope.
Can define the terms atomic number, atomic mass, mass number.
Can identify the number of protons, neutrons for an atom when given the atomic number and mass.
Can state that electrons exist within energy levels that surround the nucleus at a relatively large distance from the nucleus in comparison to
the size of the nucleus.
Can state how many electrons each energy level can hold.
Can draw the electron configuration of ground state atoms.
Can draw a generic atomic model of a ground state atom and correctly place, label and indicate the charge of the protons, neutrons and
electrons.
Score 1: With help (being given word banks, manipulated equations, retakes), the student demonstrates a partial
understanding of the simpler details and processes that support the learning goal(s) stated for a Score of 2.
Score 0: Even with help, no success
Score 4 Example Assessment Items:
Academic Vocabulary:
Explain how each of the 3 fundamental forces works to
hold an atom together. Be sure to list the relative strength
and distances over which these forces act.
List 3 similarities and 3 differences between an ion and
an isotope of Chlorine.
Draw an atomic model of 13C-2.
Score 3 Example Assessment Items:
Atom
Electric Charge
Element
Neutral
Explain the key results that were found by 2 of the
scientists that we discussed in class.
What is the role of each of the 3 fundamental forces?
How many electrons are found in the first, second, third
and fourth energy levels of the Sulfur +2 ion?
Protons
Ions
Isotopes
Atomic Mass or Mass Number
Neutrons
Electrons
ground state
energy levels
Score 2 Example Assessment Items
What is the charge and relative mass of a proton, neutron
and electron?
A _________ is an atom that has gained or lost electrons.
Draw a model of an atom correctly locating the protons,
neutrons and electrons. Make sure to label each.
Atomic Number
absorption
emission
elementary force
strong nuclear force
weak nuclear force
electromagnetic force
excited state
Achievement Scale
Content Area: Physical Science
Grade Level: 9
Unit: Atomic Structure
Learning Goals:
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I can discuss the historical developments leading to the atomic theory and analyze results of key scientists to
determine their historical conclusions.
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I can draw an atomic model and correctly label the subatomic particles and their charges.
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I can distinguish between elements ions and isotopes.
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I can discuss the role of the electron in the atoms in terms of energy levels and location in the atom.
Score 4: Student demonstrates in-depth inferences and applications of the learning goal(s) and can reconstruct and
apply their knowledge from limited information:
The student:
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Can state the timeline associated with the key theories or experiments associated with Dalton, Rutherford, Thomson, and
Bohr and how these led to the development of the atomic theory.
Can explain that the electrons are not massless but that in comparison to nucleus are insignificant to mass of the atom.
Can compare and contrast the role of the 3 fundamental forces in holding together the atom and the relative strength of each
forces (strong nuclear, weak nuclear and electromagnetic).
Can compare and contrast the terms atom, element, ion and isotope.
Can determine the number of subatomic particles in an atom when given the atomic number, atomic mass, mass number,
atomic mass unit and/or charge in symbol form.
Can identify the number of protons, neutrons and electrons for an atom, ion or isotope when given the least amount of
information possible.
Can compare and contrast the mass, charge of each subatomic particle.
Can identify the energy levels in which electrons exist when given an element, atom or ion in symbol form.
Can explain in detail what happens when electrons transfer between energy levels and the differences associated with changes
between different energy levels.
Can draw an atomic model of atoms, ions and isotopes with minimal information ( 13C-2).
Score 3: Student demonstrates no major errors or omissions regarding the learning goal(s) that were explicitly taught:
The student:
 Can state the key results of the experiments associated with Dalton, Rutherford, Thomson, and Bohr and what
this lead each to conclude.
 Can explain that the electrons are not massless but that in comparison to nucleus are insignificant to mass of the
atom.
 Can explain the role of the 3 fundamental forces (strong nuclear, weak nuclear and electromagnetic) in the atom.
 Can determine the number of each of the subatomic particles in an atom when specifically given the atomic
number, atomic mass, mass number, atomic mass unit and/or charge.
 Can state the energy levels in which electrons exist when given an atom or ion and its charge.
 Can explain that energy must be absorbed to change an atom from the ground sate to the excited state and that
this transfer (absorption or emission) happens when electrons transfer between energy levels.
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Can draw atomic models of atoms, ions and isotopes when given specific information (atomic number and mass, charge).
The Questions
What particles makes up the atom?
What is the charge on each particle?
What is the mass of each particle?
Structure of the Atom
In order to understand atoms, we need to
understand the idea of electric charge.
Electric Charge – A fundamental property of
matter that can be either positive or
negative.
We know of two different kinds of electric
charge. Positive and negative.
Structure of the Atom
Elementary Charge: The
smallest unit of electric charge
that is possible.
The elementary charge can be
either positive 1 (+1) or
negative 1 (-1) and is indicated
by the small letter, e.
The only options are whole
numbers. +1, +2, +3 (+e, +2e,
+3e)… or -1, -2, -3 (-e, -2e, 3e)…
Structure of the Atom
“Opposites Attract”
Opposite charges attract
each other and like
charges repel each other.
Positive attracts negative
charge.
Negative repels negative.
Positive repels positive.
Electric charge in matter
Electrically neutral: We say an object is
electrically neutral when its total electric
charge is zero.
The Atom
The atom is made up of 3 particles. 2 of these
particles make up the nucleus of the atom:
 Proton: A particle found in the nucleus with a
positive charge (+e) exactly equal and opposite to
the electron.
 Neutron: A particle found in the nucleus with a
mass similar to the proton but with zero electric
charge (neutral).
The third particle is found in a cloud (Electron
Cloud) that surrounds the nucleus but is far, far
away from the nucleus.
 Electron: A particle with a negative electric charge
(–e) found outside of the nucleus in the electron
cloud.
The Nucleus
The protons and neutrons
are much larger and more
massive than electrons.
The mass of the nucleus
determines the mass of an
atom because the protons
and neutrons are much
larger and more massive
than electrons.
A proton has 1,836 times
more mass than an
electron.
The Electron Cloud
Area surrounding the
nucleus.
Contains the electrons.
Does NOT contain the
nucleus.
Put it together: Model of the Atom
Nucleus: Contains Protons and Neutrons.
Electron Cloud: Contains the electrons far,
far (away) from the nucleus.
The model…
On board.
The Answers
What particles makes up the atom?
 Proton, Neutron, Electron.
What is the charge on each particle?
 Proton: +e
 Neutron: No charge.
 Electron: -e
What is the relative mass of each particle?
 Electron: 1
 Proton: 1836
 Neutron: 1839