Lecture Slides

Introduction and Overview

  • Course Title: CHEM 221 Introductory Course in Analytical Chemistry

  • Instructor Contact Information:

    • Dr. Valerie MacKenzie, Lab Manager, valerie.mackenzie@usask.ca

    • Dr. Tara Kahan, tara.kahan@usask.ca

    • Office Location: Thorv. 257

    • Office Hours: Drop in or email to make an appointment

Textbooks and Resources

  • Textbooks Required:

    • Analytical Chemistry 2.0 by David Harvey (available free online)

    • CHEM 221 Lab Manual (accessible on PAWS)

  • Course Website: Managed through PAWS

Exam Information

  • Exam Dates:

    • Midterm: Thursday, October 29th, 2024 (in class)

    • Final Exam: TBD

  • Exam Preparation:

    • Students are permitted to bring a "cheat sheet" (1 side of an 8.5 x 11 inch paper, handwritten or typed).

    • An equation sheet will be provided a week prior to exams to aid study for creating the cheat sheet.

Grading Breakdown

  • Components of Grade:

    • Canvas Quizzes: 10%

    • Labs: 30%

    • Midterm Exam: 20%

    • Final Exam: 40%

  • Exam Mark Policy: If a student performs better on the final than the midterm, the midterm score can be replaced with the final exam score. However, the midterm should not be treated as optional.

Key Concepts in Analytical Chemistry

  • Definition of Analytical Chemistry:

    • The science of conducting reliable qualitative and quantitative chemical measurements.

  • Application Example: Pregnancy tests detect Human Chorionic Gonadotropin (hCG) levels to provide quantitative data.

Importance of Analytical Chemistry

  • Relevant to various disciplines including organic, inorganic, physical, and biochemical chemistry.

  • Skills gained in this course will be valuable for future courses and may lead to job opportunities.

Challenges in Analytical Chemistry

  • There are times when necessary measurement tools are not available.

  • Example: Assessing the effects of gas stoves on indoor air quality presents challenges including noise, power requirements, size, and health concerns.

Course Objectives and Foundation Knowledge

  • Essential Background Knowledge:

    • Names and structures of common chemical substances.

    • Basic principles of stoichiometry, equilibrium, basic mathematics (especially algebra), and strong acids and bases.

  • *Concentration Definitions:

    • Concentration: The amount of solute in a known amount of solvent.

    • Expressing Concentration: Include molarity, molality, weight/volume percent, parts per million (ppm), and billion (ppb).

Concentration Measurement Techniques

  • Concentration Units:

    • Molarity (M): Moles of solute per liter of solution.

    • Molality (m): Moles of solute per kilogram of solvent.

    • Weight/Volume Percent: Useful for samples with variable molecular weights (common in polymers).

Parts per Million (ppm)

  • General definition as mass or volume ratio;

    • Example: 1 ppm corresponds to 1 g of solute in 1,000,000 g of solution (or mg/L in aqueous solutions).

Logarithmic Scales in Measurement

  • Logarithmic Measures: Used for concentrations that vary widely, particularly in hydrogen ion concentration in solutions, expressed as pH.

    • Logarithmic transformations help manage large ranges of values and improve practical calculations.

Key Definitions for Measurements

  • Accuracy vs. Precision:

    • Accuracy: Closeness to a true or accepted value.

    • Precision: Reproducibility of measurement results.

Measuring Trends and Statistical Analysis in Analytical Chemistry

  • Understanding significant figures and methods for uncertainty quantification in measurements is essential.

  • Utilize statistical tests to determine reliability and significance of measurement differences.

Application of Techniques and Concepts

  • Students will explore various measurement tools and methodologies relevant to real-world applications, including lab practices, statistics, and instrumentation.

Summary

  • This introductory course provides foundational knowledge and practical skills in analytical chemistry, focusing on measurement reliability, techniques, and statistical analysis while preparing students for both academic and professional pursuits in the field.