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Expected vs. Actual Score
Expected
Actual
• We want our expectations and performance to be as close as possible. If they are far apart, then we do not have a good grip on how well we are understanding the material!
• Exam questions are the best example of what you will see:
• Keep your exam booklet!
Hourly exams as study tools:
• On the final • On upcoming exams
• Exam questions are unique to this semester
• List the exam problems that you missed:
Hourly exams as diagnostic tools:
• This suggests that there is a specific subject that you did not understand. • Compare errors to your lecture and discussion notes.
• This could indicate a more fundamental misunderstanding of CHEM 102 so far, and you may need extra help to catch up.
• This might demonstrate that you need to slow down, review some basic math or learn how to use your scientific calculator
• Are they all on the same topic?
• Do they cover a wide variety of topics?
• Did you make calculation errors?
Re-do the problems you missed:
• The final exam is cumulative – you WILL see this material again!!
• Arrange the following atoms in order of increasing radius: Al, B, K, Mg
• Arrange the following atoms in order of increasing size: O, S, As, Se Mock Final, Fall 2013
Exam #1, Spring 2014
Decreasing atomic radius
Decr
easi
ng a
tom
ic ra
dius
Comparing the exam and the final:
• A group of chemists is studying the identity of an unknown species that has an electron configuration of 1s22s22p63s23p63d6. Which of the following is the species?
• In theory, how many different elements in the ground state can have exactly 12 electrons in various ‘s’ orbitals, exactly 30 electrons in various ‘d’ orbitals and have two or more unpaired electrons?
Mock Final, Fall 2013
Exam #1, Spring 2014
Co2+ Co3+ Fe Ni2+ Cr2-
Comparing the exam and the final:
• A group of chemists is studying the identity of an unknown species that has an electron configuration of 1s22s22p63s23p63d6. Which of the following is the species?
• In theory, how many different elements in the ground state can have exactly 12 electrons in various ‘s’ orbitals, exactly 30 electrons in various ‘d’ orbitals and have two or more unpaired electrons?
Mock Final, Fall 2013
Exam #1, Spring 2014
Co2+ Co3+ Fe Ni2+ Cr2-
6p
*Although they look different, these questions are asking the same thing – do you know how to determine electron configurations?
Questions I missed: • How many elements on the periodic table will have electrons with this set of
quantum numbers: n=4, l=2?
• Three different light sources of various wavelength strike a metal surface. Light A did not produce a photoelectron; light B and C were able to eject electrons from the metal surface, but the electron ejected by light C travels at a slower speed than light B. Which of the lights (A, B or C) has the highest frequency? Longest wavelength?
4d
Get help!
• Be prepared!
• If successive ionization energies are numbered 1, 2, 3, etc., arrange the following in increasing order of IE.
Li, (I1)
A
Na, (I1)
B
Li, (I2)
C
Be, (I2)
D
I know that ionization energy is how much energy it takes to remove an electron
I know that ionization energy increases as you move up a column in the periodic table
• What does second ionization energy mean?!?!
• Recall data mining from last week! Even if you have no idea how to start a problem, you can organize the information and determine what the question is asking for.
Do not give up!
• Use this test as an
opportunity to honestly
examine yourself and
how you are
approaching CHEM 102
• This is your chance
to make changes,
so that you
ultimately get the
result that you
want
For next week:
1) Find a partner or small group (2-3 people)
2) Pick a topic from weeks 1-4:
• Suggestions:
o Why the periodic table is awesome
o Electron configuration of elements
o Mass number, atomic number & isotopes
o Photoelectric effect
o A topic from your major
3) E-mail me your topic (sheeley@illinois.edu)
4) Prepare a 5-10 minute presentation – let me know if you need any special equipment
(whiteboards, chalk, etc.)
5) At the end of your talk, your partner/s will write down 3 questions that they have for
you, and what your answers are
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