Chemistry 2300, Quantitative Chemical Analysis
Spring 2013, 9:30-10:45 a.m., Tues. & Thur. Room 553
Dr. Marcus D. Lay, email@example.com
Phone: 542-1985, Office 520
Office Hours: 1:00 - 2:00 T & R, or by appointment. Also, feel free to email me with questions, or to set up an appointment.
Course Content: The focus of this course is quantitative chemical analysis. Therefore, we will determine the identity and concentration of a substance that is surrounded by some kind of matrix. This involves determining the best method sample it, assessing the reliability of the measurements (how the sample relates to the whole population, error analysis, etc.) and learning new analytical techniques. Course content will be largely limited to the textbook chapters listed. Complementary information, including online quizzes, spreadsheets and additional exercises with solutions, can be found at: http://bcs.whfreeman.com/qca8e/. You can also find course lecture notes, sample tests and other course information by logging into your eLearning Commons account.
Additional Help: You will have TAs from whom you can seek additional assistance. Your TAs will give you contact information during the first laboratory session. There is also the Chemistry Learning Center (CLC) on the 6th floor. This area is run by Joel Caughran and is open most of the day. There are tutors on duty while it is open. There are also computers on which you can do lab reports and homework assignments.
Questions in Class: Please feel free to ask questions, before, during and after class.
Course Text: Quantitative Chemical Analysis, By Daniel C. Harris, 8th Ed., Freeman publishers.
Grading: Your overall grade is calculated with respect to performance on class norms. The mean score is by definition a C grade. The cutoffs for B and A grades will be roughly ½ and 1 standard deviation above the class mean, respectively. The cutoffs for C and D grades will be roughly 2/3 and 1 standard deviation below the class mean, respectively. These cutoffs may change due to unforeseen circumstances. Additionally, an effort will be made to adjust the cutoffs to conform to natural gaps in grade distributions.
Your course grade will be assigned based on the exams, quizzes, final and any other assignments. The trend in your performance does not matter, although the final exam is worth 30% of your grade. If you arrive late for an exam, you may not be allowed to take the exam.
Tests: There will be four in class tests, your three highest scores will each be worth 20% of your overall grade:
Thurs., Feb. 3th
Thurs., Mar. 3th
Withdrawal Deadline: Thurs., Mar. 24th
Tues., Apr. 5th
Thurs., Apr. 28th
Final: Tues., May 10th, 8:00 - 11:00 am.
There are no “make-up” exams. If you miss an exam, then that is the one you will drop. If you miss two exams, you are in a precarious situation.
I generally make the tests difficult so that people who work hard can show it. The result is that if you do not study very much for this class, you may have big problems.
The Final will be worth 30% points. It will be a standardized ACS final exam. This will demonstrate your level of comprehension with respect to other Quantitative Chemical Analysis students around the country.
Please do not embarrass yourself by grade grubbing, which is complaining that you need a better grade for some purpose like your perfect GPA, to keep your scholarship, or to graduate. Your grade will reflect your level of work in this course, not any outside influences. Work hard from the start, as small differences in performance can make a big difference in your grade.
Homework: There will be a series of homework assignments from the textbook. I encourage you to read ahead and start the homework problems before we cover a topic in class.
Quizzes: There will be a series of unannounced in-class quizzes, worth a total of 10% of your grade. These are usually derived from the assigned homework problems and/or previous lectures.
Attendance: Important announcements about the course will occasionally be made in class. You are responsible for knowing this information, even if you are not in class. Lecture notes are periodically handed out in class. If you are not present, it is your responsibility to obtain a copy.
Laboratory Reports: You will be expected to use a word processor and spread sheet for your all of your laboratory reports. You can get help with excel in the Chemistry Learning Center (CLC) or on the web:
Labs: Professor Marcus D. Lay will be in charge of the labs.
TAs: Dovie Stanley and Darya Asheghali.
The labs for Quantitative Analysis start next Monday, even if some signs in the hall tell you that chemistry labs start later. You will be assigned a lab grade that is independent of your class grade. Your TA will give you information about grading policies for the lab. Each lab is graded independently, so comparing average grades in each lab section is not at all useful.
For lab, you will need a lab book with carbon paper, so you can hand in a copy of your lab notes each day. You can get a copy of the lab experiments from this course’s eLearning Commons page.
****You will also need safety goggles. These can be purchased from the stockroom.****
Course Outline: It is my intention to follow the book in the following sequence to ensure that we cover topics before related laboratory experiments:
Chapter 0: This is an introduction to chemical analysis. It describes sampling, and how we go about doing an analysis. There is also some review material that we will cover briefly, but you will be responsible for, like calibration curves and general steps in a chemical analysis.
Chapter 1: SI units, the unit factor method, calculations of concentration, and the preparation of standard solutions. Chemical concentrations, preparing solutions, solution stoichiometry and introduction to titrations.
Chapter 2: There is a section on safety and how you handle chemicals. This is the most important section in the book. We try to structure the labs to be safe, but exercise care when dealing with concentrated reagents and protect yourself at all times. This chapter also covers tools commonly used in an analytical laboratory. You should read this material before you attend your first lab.
Chapter 3: Introduction to experimental error, where it comes from, what kinds there are, how to reduce it and how to take it into account. Determinate error can be removed, but indeterminate error is always present in every measurement. There are also sections on propagation of errors in successive calculations.
Chapter 4: Statistics. Since we can’t get rid of indeterminate errors, we use statistics to account for them. We will cover Gaussian distributions, and the statistics of small sets of numbers. We will learn about the student t test to help us determine how much confidence to put into our numbers. We will use a Grubbs test to see if we should keep data that looks suspect. We will learn about how you draw a best straight line in a set of data using the method of Least Squares.
Chapter 5: Calibration methods. Techniques such as external standard, standard addition and internal standards allow us to get reproducible and accurate results.
Chapter 6: This chapter involves chemical equilibria, and is in part a review of material you studied in General Chemistry. However, in this course the emphasis will be on the types of equilibria that must be considered for various types of analysis. We will start with a review of equilibrium constants, thermodynamics and Le Chatelier's principle. Then we will consider solubility product constants. These are important in gravimetric analysis, where we precipitate a compound and weigh it to determine how much of a component is present. The common ion effect will be discussed as it helps us obtain more complete precipitation of an analyte. We will also learn about acid-base chemistry.
Chapter 7: Activity: How the concentration of ions affects the tendency for species to interact. The “effective concentration” frequently deviates from what you expect it to be. The effect of a solutions ionic strength on the solubility of ionic salts.
Chapter 26: Gravimetric analysis. Using mass measurements to determine how much of something is present.
Chapter 8: Monoprotic acid-base chemistry. Buffers and buffer capacity.
Chapter 9: Polyprotic acid-base chemistry. Equilibria equations. Fractional composition.
Chapter 10: Acid-base titrations. Graphical treatments of various forms of acid-base titrations. Instead of using an indicator to find the endpoint, you can make a graph of pH vs. volume of titrant added. We will cover how to use the derivative of a titration curve for endpoint determination.
Chapters 17 & 18: Go toward the light. Light can be used to perform analysis. We refer to this as spectrophotometry. If an analyte turns a solution green, then a solution that is light green contains less of it than one that is dark green. Beer's law is a way of saying this in a quantitative way.
Chapter 22: Introduction to analytical separations and high performance liquid chromatography (HPLC). Separate and quantitate solutes based on their affinity for a mobile vs. a stationary phase; theory and applications.
Chapter 23: Gas chromatography. More on the separation process. Injection ports and detectors.
Lecture Handout: The atomic force microscope (AFM) is used to obtain quantitative information about systems that are too small to be visualized by other types of microscopes.
Chapter 13: Electrochemists get a charge out of things. Fundamentals of electrochemistry, standard potentials, batteries, reference electrodes, the Nernst equation, other basic concepts.
Chapter 14: Ion-selective electrodes, the pH electrode, junction potentials.
Chapter 15: Electroanalytical techniques, i.e. electrogravimetric analysis and cyclic voltammetry.
We expect students at the