Download unit 7 hw packet File

AP CHEMISTRY
Name _____________________
Unit #7 Plan / HW Packet – Atomic Structure and Periodicity
I)
Assignments
A)
Study chapter 7 in text
B)
Complete chapter 7 “interactive review exercises” (science geek website)
C)
Complete chapter 7 “interactive practice exercises” (SGweb):
 Quantum numbers --- as needed
D)
Study chapter 7 summary handout
 Complete self assessment (answers posted on moodle)
E)
Chapter 7 HW problems (hw packet)
F)
Chapter 7 Text problems (do on your own paper)
Text Problems: 38, 46, 59, 82, 92, 104, 108, 110, 117, 162, 163
Show supporting work. Give clear explanations.
Google “You tube senior physics structure of the atom 1”
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II)
Repeat for 2,3,4,5,6 (especially 3-6)
Each is a about a 9 minute video clip with narration
Senior Physics Structure of the Atom Series
Learning Targets (I can …)
A. Analyze the relationship between energy, frequency, and wavelength of light (both
qualitatively and quantitatively).
B. Compare and contrast different regions of the electromagnetic spectrum.
C. Distinguish between ground state and excited state electrons.
D. Explain how spectral lines can be used to identify elements and reveal information about
the electron structure of elements.
E. Explain the Bohr model of the atom and identify its advantages and limitations.
F. Describe electron motion based on the Schrödinger equation and the Heisenberg
uncertainty principle.
G. Describe the photoelectric effect and how it relates to atomic structure and the dual
nature of light.
H. Identify and compare electron orbitals (s, p, d, f).
I. Write electron configurations for both neutral atoms and ions using the Aufbau principle,
Pauli exclusion principal, and Hund’s rule.
J. Use electron configurations to predict chemical trends and behaviors of elements.
K. Determine the quantum numbers of a given electron or determine the location of an
electron given its quantum numbers --- not required
L. Identify and explain trends in the periodic table (ionization energy, electron affinity, and
atomic radius).
M. Make predictions about the behavior of elements based on these periodic trends.
N. Use data from photoelectron spectropscopy (PES) to identify elements.
III) Terms, Equations, and Formulas (see AP formula sheet)
Terms
A)
B)
C)
D)
E)
F)
G)
H)
Orbital – place where electrons are likely to be found.
Node – place where electrons are not found.
Aufbau principle – electrons fill lowest energy levels first.
Pauli exclusion principle – maximum of 2 electrons in one orbital. Two
electrons in one orbital will have opposite electron spin.
Hund’s rule – electrons filling an orbital set (degenerate orbitals) will have
the same spin and fill different orbitals until the orbital set is half full.
Heisenberg uncertainty principle – can not know exact momentum (speed)
and location of an object at the same time. This applies to very small
objects such as electrons.
Wave nature – explains diffraction of an electron.
Particle nature – massless particles called photons carry energy.
Equations and Formulas
E = hν or ΔE = nhν (n = an integer)
λν = c
E = mc2
λ = h / mν (de Broglie’s wavelength)
E = IE(1/n2initial – 1/n2final)
E = Energy (measured in kilocalories or kilojoules --- 1.00 kcal = 4.18 kjoules)
ν = Frequency --- number of waves that pass a given point in a specific time
(measured in hertz or cycles/second)
λ = Wavelength --- the distance between corresponding points on adjacent waves
(measured in meters, centimeters, nanometers, etc)
c = Speed of light constant (3.00 and 108 m/sec)
m = mass
h = Planck’s constant (3.99 x 10-10 joule sec / mol or 6.63 x 10-34 joule sec)
IE = Ionization energy (measured in kjoule/mol)
n = Energy level number (an integer)
IV) Tentative Schedule
Wed 11/11 Qt #2 final exam – FRQ
Chapter 7 reading / science geek
Thu
11/12 Atomic structure review / overview;
Chapter 7 summary handout
Fri
11/13 Socratic check
Mon 11/16 Photoelectron spectroscopy (PES) lab
Tue
11/17 Periodic trends
Wed 11/18 Review
Thu
11/19 Exam #7; HW packets/problems due
Socratic Check – Think about these questions. Do research as needed. Be ready to
discuss during class. Record your thoughts.
1. At what speed does electromagnetic radiation travel?
2. Are the following relationships for electromagnetic radiation direct or inverse?
Wavelength and frequency
Wavelength and energy
Frequency and energy
3. Max Planck concluded that energy is “quantized”. What does this mean?
4. What is a photon?
5. What is the photoelectric effect?
6. What was de Broglie’s hypothesis?
7. What is meant by the “dual nature of light”?
8. How did Bohr explain the line spectra of the hydrogen atom?
9. What are the limitations of Bohr’s “planetary” model of the atom?
10. Describe Schrodinger’s quantum mechanical model of the atom?
11. Is a “2s” electron in an atom (always, usually, usually not, or never) further from
the nucleus than a “1s” electron in the same atom? Explain.
12. What is meant by the Heisenberg uncertainty principle?
13. Why do atoms in an orbital have opposite electron spin?
14. Which electron has the most (and least) energy in an atom? (4s, 4p, 4d, or 4f)
Explain your choices.
15. What is meant by “electron shielding”?
16. What is meant by “effective nuclear charge”?
17. What is the distinction between paramagnetic, diamagnetic, and ferromagnetic?
Unit #7 homework problems
Attempt these problems after doing the homework problems in your text. They can serve as a
review. Core concepts from unit 2 are mixed in as well.
1.) Ernest Rutherford’s gold foil experiment demonstrated the existence of the
(A) alpha particle
(B) photon
(C) neutron
(D) nucleus
(E) proton
2.) The removal of an electron from which gaseous atom requires the greatest amount of energy?
(A) Na
(D) Cl
(C) K
(D) Br
(E) Li
3.) For which pair of species is the difference in radii the greatest?
(A) Li and F(B) Li+ and F+
2(C) Li and O
(D) O2- and F+
2(E) Na and O
4.) The electron configuration of cobalt (Z=27) is 1s22s22p63s23p64s23d7. How many unpaired
electrons are in a gaseous Co3+ ion in its ground state?
(A) 0
(B) 2
(C) 4
(D) 6
(E) 8
5.) How many valence electrons are in a persulfate ion, SO52-?
(A) 32
(B) 34
(C) 36
(D) 38
(E) 40
6.) Which has the highest ionization energy for the removal of the second electron?
(A) F
(B) O
(C) Na
(D) Mg
(E) Ca
7.) What is the wavelength of a photon with the energy of 6.51 x 10-21 J?
(A) 3.05 x 10-5 m
(B) 9.82 x 1012 m
28
(C) 4.61 x 10 m
(D) 2.17 x 10-29 m
-7
(E) 3.05 x 10 m
8.) Which of the following compounds is
chromium (III) oxide?
(A) CrO
(B) CrO2
(C) Cr2O
(D) Cr3O2
(E) Cr2O3
9.) In a hydrogen atom, which transition produces a photon with the highest energy?
(A) n=3n=1
(B) n=5n=3
(C) n=12n=10
(D) n=22n=20
(E) n=3n=2
10.) J.J. Thomson used which piece of laboratory equipment to discover the electron?
(A) Buret
(B) Filter Flask
(C) Positive electrode
(D) Cathode Ray
(E) Gold Foil
11.) What is the correct ground state electron configuration for the chromium atom?
(A) [Ar]4s13d3
(B) [Ar]4s23d4
1
5
(C) [Ar]4s 3d
D) [Ar]3d4
2
2
(E) [Ar]4s 3d
12.) What is the correct ground state electron configuration for the Cr +2 ion?
(A) [Ar]4s13d3
(B) [Ar]4s23d4
1
5
(C) [Ar]4s 3d
(D) [Ar]3d4
2
2
(E) [Ar]4s 3d
13.) What is the maximum number of electrons that occupy the n=3 level?
(A) 6
(B) 8
(C) 10
(D) 18
(E) 2
14.) Which atoms has the largest atomic radius?
(A) Li
(B) K
(C) As
(D) Br
(E) Na
15.) Which quantum numbers represent the orbitals being filled in the ground state for the
elements Sc (21) to Zn (30)?
(A) n=3, l=1 (B) n=3, l=2
(C) n=4, l=1
(D) n=4, l=2 (E) None of the above
16.) Which pair consists of species that are isoelectronic?
(A) Na+, K+
(B) Cl, Cl(C) Fe2+, Mn2+
(D) Ar, Ca2+
(E) None of the above.
17.) Which properties of electromagnetic radiation are inversely related?
(A) wavelength and frequency
(B) energy and wavelength
(C) energy and frequency
(D) none of the above
(E) both A and B
18.) Which of the following is diamagnetic?
(A) Li
(B) Mg
(C) O
(D) F
(E) Pt
19.) Which element most readily gains an electron (has the most negative electron affinity)?
(A) F
(B) Na
(C) Cs
(D) Ne
(E) I
20.) Which element most readily loses an electron (has the least positive ionization energy)?
(A) F
(B) Na
(C) Cs
(D) Ne
(E) I
Free Response - Answer the following questions accurately. Explanations should be clear and
well organized. Cite examples and/or equations if appropriate. Specific answers are
preferable to broad, diffuse responses.
1997D
1.) Explain each of the following observations using principles of atomic structure and/or
bonding.
(a) Potassium has a lower first-ionization energy than lithium.
(b) The ionic radius of N3- is larger than that of O2-.
(c) A calcium atom is larger than a zinc atom.
(d) Boron has a lower first-ionization energy than beryllium.
1987D
2.) Use the details of modern atomic theory to explain each of the following experimental
observations.
(a) Within a family such as the alkali metals, the ionic radius increases as the atomic
number increases.
(b) The radius of the chlorine atom is smaller than the radius of the chloride ion, Cl -. (Radii
: Cl atom = 0.99Å; Cl- ion = 1.81 Å)
(c) The first ionization energy of aluminum is lower than the first ionization energy of
magnesium. (First ionization energies: 12Mg = 7.6 ev; 13Al = 6.0 ev)
(d) For magnesium, the difference between the second and third ionization energies is
much larger than the difference between the first and second ionization energies.
(Ionization energies for Mg: 1st = 7.6 ev; 2nd = 14 ev; 3rd = 80 ev)
2008A
3.) Using principles of atomic and molecular structure and the information in the table below,
answer the following
questions about atomic fluorine, oxygen, and xenon, as well as some of their compounds.
Atom
F
O
Xe
First Ionization Energy (kJ / mol)
1,681.0
1,313.9
?
(a) Write the equation for the ionization of atomic fluorine that requires 1,681.0 kJ mol−1.
(b) Account for the fact that the first ionization energy of atomic fluorine is greater than that
of atomic oxygen. (You must discuss both atoms in your response.)
(c) Predict whether the first ionization energy of atomic xenon is greater than, less than, or
equal to the first ionization energy of atomic fluorine. Justify your prediction.