CHEM144 Chemical Reactions, Separations and Identifications

Department of Science, Technology, Engineering & Mathematics: Chemistry

I. Course Number and Title
CHEM144 Chemical Reactions, Separations and Identifications
II. Number of Credits
4 credits
III. Number of Instructional Minutes
IV. Prerequisites
CHEM101 (B or better), or CHEM121 (C or better), or a grade of C or better in both CHEM101 and CHEM102
V. Other Pertinent Information
Three-hour lecture and three-hour laboratory per week.
VI. Catalog Course Description
This lecture and laboratory course is an introduction to the methods and underlying principles involved in the separation and the identification of the components of a mixture. Methods used include selective precipitation, redox, and complex ion formation in solution. Principles affecting the rate and limit of reactions are stressed.
VII. Required Course Content and Direction

This is the first of the chemistry courses that deals exclusively with analytical chemistry. It is designed to meet the needs of those students who have completed at least one semester of first year college chemistry, either Chemistry I or Chemistry A, and who require, in their programs of study, knowledge of the principles and methods dealing with the separation and qualitative identification of the components of a mixture. Analytical Chemistry is concerned with chemical composition. This course concerns itself with what is present. How much is present is studied in Quantitative Analysis.

This course is designed for students enrolled in the following programs of study: Chemical Laboratory Technology, Chemistry, and Engineering (Chemical). Students who plan to pursue careers in health-related technologies or environmental science will also find this course of value.

As one of the Natural Sciences, chemistry has evolved out of careful observation and experimentation; as technology evolves, so does the body of chemical knowledge. This course will integrate relevant technological advances and their impact in the formulation of chemical principles and their applications. Furthermore, the laboratory component of the course will help to illustrate and apply some of these technological advances.

The major focus of the course is the study of the separation of mixtures of common cations and anions from aqueous solutions. The unique chemical and physical properties of these ions are used as a basis for their identification. Major emphasis is placed on the study of heterogeneous and homogeneous equilibria in chemical systems and the laws, theories, and principles that govern chemical equilibria in aqueous solution. The dynamic character of chemical equilibria and the experimental conditions that influence the direction in which the equilibria will shift are also emphasized. Le Chatelier's principle and the process of precipitation are studied in terms of the theory of nucleation and the experimental conditions that favor or interfere with precipitation. Stress is placed on the sources of contaminants and appropriate methods for their removal from precipitates. The separation and identification of cations and anions, and experiments dealing with chemical equilibria, constitute the laboratory portion of the course.

  1. Course Learning Goals

    Students will:

    1. recognize the physical laws that govern chemical equilibria. These include: mass action, thermodynamics, and the conservation of mass, energy, and charge;
    2. describe the properties of chemical systems and predict their chemical behaviors by application of the Periodic Law of the Elements. Systems studied include acids, bases, and salts;
    3. describe and evaluate the dynamic character of chemical equilibria by using models proposed for solvation, precipitation, chelation, and complexation; and
    4. demonstrate basic laboratory skills as they pertain to: safety, management of both qualitative and quantitative work, ability to draw conclusions from experiments, and understanding the importance of technological advances and scientific knowledge.
  2. Planned Sequence of Topics and/or Learning Activities

    Course Outline:

    1. Introduction to Qualitative Analysis
    2. Nature of Chemical Reactions
      1. Kinetics
      2. Chemical Equilibrium
      3. Thermodynamics
    3. Nature of Chemical Compounds
      1. Physical Properties
      2. Classification
      3. Ionization of Water
      4. Acids and Bases
    4. Solution Phenomena
    5. Complex Compounds
    6. Oxidation-Reduction Reactions
    7. Practical Aspects of Qualitative Analysis
      1. Periodic Table
      2. Chemical Reactions
      3. Equilibrium Considerations
      4. Formation of Precipitates
      5. Dissolving Precipitates
    8. Silver Group
    9. Copper-Arsenic Group
    10. Aluminum-Nickel Group
    11. Barium-Magnesium Group
    12. Analysis of Anions
    13. Analysis of Alloys
    14. Analysis of Salts and Salt Mixtures
    15. Chromatography Techniques

    Laboratory Experiments:
    While specific laboratory experiments vary depending on the instructor and the semester, the following list is representative of the experiments that are used:

    1. Safety Practices in the Chemistry Laboratory
    2. Demonstration of Laboratory Techniques
    3. Studying Chemical Equilibria and Applying Le Chatelier's Principle Using Microscale Techniques
    4. Determining Dissociation Constant of a Weak Acid Using pH Measurements
    5. Determination of the Solubility Product Constant of a Salt
    6. Determining an Equilibrium Constant Using Spectroscopy
    7. Paper Chromatography of Selected Metal Ions
    8. Use of an Anion Exchange Column and AA for the Separation and Identification of Cobalt (II), Iron (III), and Nickel (II)
    9. Silver Group
    10. Copper-Arsenic Group
    11. Aluminum-Nickel Group
    12. Barium-Magnesium Group
    13. Anions
    14. Inorganic Qualitative Analysis

    Learning Activities:
    Instruction aims to enable the student to:

    1. learn to separate cations and anions and to identify them by applying basic chemical principles;
    2. become aware of the potential sources of contaminants and the need to prevent the introduction of them into the sample;
    3. become aware of the ways that various contaminants can alter the results, as well as the validity of the results;
    4. understand the physical laws that govern chemical equilibria. These include: mass action, thermodynamics, conservation of mass, energy, and charge;
    5. describe the properties of chemical systems and predict their chemical behaviors by application of the Periodic Law of the Elements. Systems studied include acids, bases, and salts;
    6. describe and understand the dynamic character of chemical equilibria. Models are proposed for solvation, precipitation, chelation, and complexation using:
      1. A conceptual model of an ideal system in the analysis.
      2. The basic assumptions that apply to the model.
      3. The operational parameters of the model.
      4. The limitations in the application of the principles of the model to the real system;
    7. perform experiments, to make observations using human senses, and to evaluate the results including their reliability; and
    8. obtain a better understanding of the importance of technological advances for the development of scientific knowledge, and apply these advances in the laboratory when appropriate.
  3. Assessment Methods for Course Learning Goals

    Course learning goals will be continuously assessed by periodic written examinations, class exercises, laboratory preparation, laboratory results, laboratory reports, and assigned work.
  4. Reference, Resource, or Learning Materials to be used by Student:

    Students will use the approved text, laboratory modules and handouts, laboratory and demonstration equipment, the library, science learning center, and computer programs. Please refer to the course format for specific information.

Review/Approval Date - 2/99; Revised 6/08; New Core 8/2015