Download APPENDIX 2 1 ASSESSMENT OF STUDENT LEARNING BROAD

APPENDIX 2
ASSESSMENT OF STUDENT LEARNING
BROAD LEARNING GOALS
I.
Assessing Data Analysis Skills
II.
Assessing Molecular Representation
III.
Assessing Basic Measurement Skills
IV.
Assessing Knowledge of Intramolecular and
Intermolecular Forces
V.
Recognizing the Properties of Substances:
Structure/Property Correlations
VI.
Assessing Knowledge of Solutions
VII.
Assessing Understanding of How to Separate Compounds
VIII.
Assessing Understanding of Atomic, Molecular and
Macromolecular Sizes.
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APPENDIX 2
ASSESSMENT OF STUDENT LEARNING
CONCEPTS ASSOCIATED WITH BROAD LEARNING GOALS
I. Assessing Data Analysis Skills
Concept
Level
Working knowledge of terminology and conventions (e.g., meaning
of abscissa and ordinate, knowing that P vs. V means that P is
the ordinate and V is the abscissa, meaning of positive and negative
correlation, meaning of direct and inverse proportion)
first-year
Interpretation of graphed information
first-year
Elements of graphical style (e.g., maximizing use of graph area,
choosing effective scales)
first-year
Use of graphing software (for obtaining quantitative information,
although initial sketching of graphs by hand will be encouraged to
maintain literacy)
first-year
Use of spreadsheet software
first-year
Sketching trendlines (estimating a best-fit curve by eye)
first-year
Working knowledge of basic statistics (mean, standard deviation,
median, confidence limits, t-test)
junior/senior
Fitting trendlines (calculating a best-fit curve using least-square
methods)
junior/senior
Evaluating goodness-of-fit of a trendline (proper use of correlation
Coefficient, testing the null hypothesis that a fit parameter differs
from zero)
junior/senior
Most of the concepts are listed at the first-year level not because students will have
mastered them that soon but rather because they should be introduced to them in the
first year. This notion is guided by graphs found in typical general chemistry books and
by opportunities for graphical data analysis in the existing CHEM 2115 (Chem I Lab)
experiments. Facility with any particular concept can be assessed at several levels of
sophistication if the assessment instruments are designed well.
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APPENDIX 2
II. Assessing Molecular Representation
Concept
Level
Condensed formula
Molecular formula
Empirical formula
Formulas of hydrates
Formulas of ionic vs. covalent compounds
Charges on ions
Space filling models
First-year
(Chem I)
Formulas showing all bonds (recognizing types of bonds)
Partially condensed formulas
Formulas of particles (these are not whole molecules, but parts
of molecules)
Functional group representation
Line formulas
Formulas showing stereochemistry (Fischer, Cram, Newman)
Space filling models
Formulas of coordination complexes
First-year
(Chem II & III)
Chem IV & Inorganic
Formulas of macromolecules
3-D representation of macromolecules
Representation of enzyme active sites and protein binding sites
Biochemistry
Formulas of transient species for calculations of energy of
different conformers
P Chem.
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APPENDIX 2
III. Assessing Basic Measurement Skills
General
Understanding that a measurement is subject to experimental error and therefore needs
to be reproduced (Understanding systematic vs. random errors, propagation of error)
Understanding how many digits are necessary to express the results of the
measurement to the precision with which it was made.
Understanding the difference between precision and accuracy
Understanding what it means when asked to measure temperature to ± 0.1oC, or mass
to ± 0.001 g.
Understanding where the uncertainty lies in a measurement when reading scales.
Understanding that a measurement is made up of a numerical value that is inextricably
linked to a unit of measurement.
Understanding the magnitude of an experimental value (e.g. checking that it makes
sense).
Experimental
Knowing what glassware to use when asked to measure different volumes
Knowing that glassware are calibrated differently to measure either approximate
volumes or very specific volumes. Knowing the difference between glassware calibrated
to contain or deliver volumes.
Understanding the differences between the various balances and knowing which to use
based on the mass to be measured.
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APPENDIX 2
IV. Assessing Knowledge of Intramolecular and Intermolecular Forces
Concept
Level
Electron-electron repulsion, electron-nucleus attraction and
atomic structure
first-year
Electron-electron repulsion, molecular geometry, and polarity
first-year
Types of intermolecular forces (ion-ion, ion-dipole, dipole-dipole,
induced dipole-dipole, induced dipole-induced-dipole) and
their relative strengths
first-year
Intermolecular forces and states of matter
first-year
Intermolecular forces and trends in vapor pressure and boiling point
first-year
Hydrogen bonding and the anomalous properties of water
first-year
Intramolecular forces and conformational isomers
sophomore
Role of intramolecular hydrogen bonding in determining molecular
structure (DNA double helix, α-helix)
junior
Hydrophobic effect
junior
Anomeric effect
junior
Molecular interpretation of nonideal gas properties
junior/senior
Relationship between molecular interactions and chromatography
junior/senior
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APPENDIX 2
V. Recognizing the Properties of Substances: Structure/Property Correlations
Concept
Level
Recognizing the nature of a compound
Ionic and covalent compounds
Organometallic compounds
Electron-deficient compounds
Coordinate complexes
Sugars amino acids and macromolecules
Chem I, II
Chem II, III, Inorg?
Chem I, II, Inorg
Inorganic
Chem II, III, Biochem
Recognizing physical properties
Correlating structure to melting point and boiling point
Effect of impurities on mp and bp of compounds
Density, vapor pressure, diffusion, osmosis
Recognizing acids and bases
Lewis and Bronsted-Lowry definitions
Correlating pKa to acidity; pH, Conjugate acids and bases
Identifying “acidic” and “basic” centers in a given molecule
Correlating structure to acidity and basicity
Chem I, II, III
Chem II, III, IV?
Chem I, IV?
Chem I, II
Chem I, II, IV
Chem II, III
Chem I, II, III,
Adv.Org. Chem
Recognizing polar and non-polar compounds
Concept of dipole and dipole moment
Understanding that polarity is a consequence of charges
or net dipole present
Evaluating the solubility of a compound in a particular solvent
based on polarity
Chem I, II
Recognizing nucleophiles and electrophiles
Definition of a nucleophile and electrophile
Identifying “electrophilic” and “nucleophilic” centers
Drawing correct electron shift arrows
Nucleophilicity and basicity; the variation depending on the
nature of the solvent used
Chem II
Recognizing structural properties
Presence (if any) of isomerism, resonance, tautomerism,
aromaticity, epimerisation and zwitterionic existence of a
molecule
Chem II, III, Adv.
Org.Chem, Biochem
Chem II, III, Adv.
Org.Chem, Survey
of Instr? Lab Methods?
Recognizing spectroscopic properties
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APPENDIX 2
VI. Assessing Knowledge of Solutions
What is a solution and what does it look like?
How is a solution different from a pure liquid?
Solutions can be made in one or two ways:
a) Diluting a more concentrated solution
b) Dissolving a solute in a liquid
In order how to figure out how to do (a), need to know what volume of the more
concentrated solution is needed to make the dilute solution. In order to do (b), it
is necessary to know the mass of the solute.
Solutions are usually discussed in terms of concentration or the amount of solute. There
are several ways to define this, including:
a) molarity
b) %
c) (5x, 10x, 50x)
d) normality
What are the units for each of these types of solutions?
Do all these units apply to solutions made from either dilution of stronger solutions or
from the solid? Molarity and normality can be done for either type of solution, but % is
for solutions prepared from solids only and 10x is for dilutions only
How are these calculations done? Students should be able to solve either for mass or
volume for any type of solution given its concentration and the volume desired
What happens chemically when a solute is mixed with a solvent? Is there a chemical
reaction, a dissociation, or no change in the solute? Why do different solutes do
different things?
What is the solvent? Most commonly it is water and what special properties does water
have to make it such a common solvent? (This is especially true when discussing
biological solutions)
Can chemical reactions occur when solutions are mixed together? Does this ever occur
or does it never occur and on what does it depend?
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APPENDIX 2
VII. Assessing Understanding of How to Separate Compounds
What is the difference between a mixture and a contaminant? A mixture means more
than one molecule is present in significant amounts and a contaminant means one or
more molecules are present in small amounts
The purification scheme used will be different if it is a mixture or a contaminant (There is
an excellent example of this in Chem II Lab) Why is this so?
What does it mean to completely purify a compound? How is it possible to know if this
has occurred? The answer varies depending on what the compound is: organic
molecule, protein, DNA, etc.
Do methods to remove contaminants take advantage of specific properties of
contaminants or do they work in general?
To separate a compound from a mixture, what methods can be used and what
properties do they take advantage of in the molecule? This is the opportunity to discuss
the various types of chromatography, how they work and what property is being
exploited in the compound (size, charge, polarity, etc.)
Since chromatography is essentially always a way of separating compounds, the
various types should be discussed.
In all of these separation methods, is the molecule being chemically altered? Are any
chemical reactions occurring?
Why is it necessary to frequently use more than one method to separate a mixture and
what, if anything, determines the order of the methods?
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APPENDIX 2
VIII. Assessing Understanding of Atomic, Molecular and Macromolecular Sizes
1. Understanding how protons, neutrons and electrons contribute to atomic size.
2. Understanding how the size of atoms changes with increasing atomic number.
3. Comparing the sizes of neutral atoms with their ion counterparts. Predicting the sizes
of ions depending on their charge (+ or -).
4. Visualizing the three-dimensional structure of substances such as ionic compounds
and molecules to scale. For example, lithium iodide, CH3OH and glucose compared
to H2O.
5. Understanding the relationship between molecular size and MW (g/mol or Daltons)
6. Understanding that the size of a molecule depends on the number and size of the
bonded atoms that make it up.
7. Understanding what Van der Waals radii represent in the space-filling models of
molecules.
8. Understanding relative sizes in the structural hierarchy from the atomic to organism
level (atoms → molecules → macromolecules → supramolecular assemblies →
organelles → cells → tissues → organs → organism). Using powers of 10 to illustrate
this hierarchy.
9. Understanding that macromolecules (DNA, protein, glycogen) are made up of
smaller molecular building blocks (nucleotides, amino acids, glucose)
10. Knowledge of methods for separating molecules, macromolecules, supramolecular
assemblies and organelles based on size. Chromatography, centrifugation,
electrophoresis, dialysis.
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