CH271
Exam 3 Study Guide
Exam covers chapters11, section 12-5, 13 (sections 13-1 to 13-4 only), 18, and 19 (sections 19-1 to 19-4 only), the handout on fractional composition, and the potentiometric chloride lab experiment handout (as it pertains to potentiometry).
You can expect the quantitative analysis exams to include both calculation problems and conceptual questions. Because of the nature of the course, the exam will be weighted more heavily towards calculations. Typically 65-80 percent of the total points possible will be based on calculation problems.
You should:
1) Know and be able to explain or define the important terms listed at the end of each chapter.
2) Know the important concepts and principles introduced earlier in the course, i.e. concentration, dilution, stoichiometry, equilibrium, basic SI units and prefixes, significant figures,acid and base chemistry, buffers, titrations, etc. Be able to calculate concentrations and the results of dilutions.
3) Be able to calculate the pH for solutions containing polyfunctional acids and bases, as well as solutions containing species derived from them.
4) Be able to calculate the pH for solutions containing buffers derived from polyfunctional acids and bases.
5) Be able to calculate the pH at any point during the course of an acid-base titration involving aweak polyprotic acid-strong base, and a weak polyfunctional base-strong acid.
6) Understand how to determine the end point from a titration curve, first derivative curve, and second derivative curve.
7) Be able to calculate the fractional composition of a weak acid or base solution as a function of pH. (Do not memorize the equations, but know how to use them and what they mean.)
8) Be able to predict the principle species derived from a weak acid or base (both polyfunctional and monofunctional) present in a solution at any given pH.
9) Understand and be able to explain the purpose of auxiliary complexing and masking agents, and how pH can be used to control selectivity of complexometric titrations.
10) Understand and be able to explain how metal ion indicators function.
11) Understand the different EDTA titration techniques.
12) Be able to calculate the results for complexometric titrations.
13) Understand the basic properties of light, and be able to perform basic calculations of energy, frequency, and wavelength given appropriate information.
14) Understand the concept of absorption of light and what happens when UV-visible light is absorbed by an analyte, i.e. what happens to the analyte when light is absorbed.
15) Be able to calculate absorbance from transmittance and visa versa.
16) Understand Beer’s law and be able to perform calculations involving it.
17) Understand and be able to explain the relationship between absorption of visible light and color.
18) Calculate the results of a spectroscopic experiment based on Beer’s law using the single standard and calibration curve methods.
19) Understand and be able to explain why the spectrometer is “zeroed” with a blank prior to making absorbance readings, as well as good operating techniques.
20) Based on the reading in chapter 19, generally know what each of the following components in a spectrophotometer does: Light source, monochromator, detector. Know the basic difference between dispersive spectrophotometers and a diode array spectrophotometer.
21) Be able to explain what an isosbestic point is and what it indicates.
22) Understand what a redox reaction is and how it may be used to generate electricity in an electrochemical cell.
23) Know the basic components in an electrochemical cell and a potentiometric cell.
24) Be able to perform calculations of potential using the Nernst equation; be able to apply the Nernst equation.
25) Be able to calculate the concentration of an analyte based on potential measurements given appropriate information.
26) Understand the difference between the indicator electrode and reference electrode.