1. Chapter 4: Calculations Used in Analytical Chemistry CHE 321: Quantitative Chemical Analysis Dr. Jerome Williams, Ph.D. Saint Leo University

2. Overview Units & SI System Moles & Millimoles Solutions: Expressing Concentration Stoichiometry

3. Units & SI System Units convey information and serve as guide to solving problems – Fundamental Units – Derived Units

4. Table 4-1 p63

5. Units & SI System Measurements based on SI system, which is metric system – Metric Prefixes – Performing Unit Conversions (see Tutorials)

6. Table 4-2 p63

7. Moles & Millimoles Mass versus Weight Moles are the SI unit for amount of a substance. One mole of anything contains Avogadro’s number of particles (chemical formula)

8. p64

9. Moles & Millimoles Molar Mass is mass in grams of one mole of a substance. Calculate molar mass by summing atomic masses of all elements in formula. Often more convenient to use unit millimole (Note: 1 mmole is equivalent to 10 -3 mole)

10. p65

11. Moles & Millimoles Review Examples 4.1 & 4.2 Complete Tutorials

12. Solutions: Expressing Concentration Review definitions of analytical molarity, and equilibrium molarity – Equilibrium concentrations expressed as molarity – Analytical concentrations use formal concentration Review Examples 4.4 – 4.6 Review Tutorials

13. Solutions: Expressing Concentration Percent Concentration - review definitions & formulas for the following – Mass (Weight)% – Volume % – Weight/volume % – Parts per Million (ppm) – Parts per Billion (ppb) Go over example problems & complete tutorials

14. Solutions: Expressing Concentration Review definitions of p-Functions pX = - log [ X ]

15. Solutions: Expressing Concentration Review definitions of density and specific gravity Density = mass / volume M 1 V 1 = M 2 V 2

16. Figure 4-1 p74

17. Table 4-3 p74

18. Stoichiometry Quantitative relationship among reactants & products in a balanced chemical reaction. Review Empirical vs. Molecular Formulas Review Structural Formulas

19. Figure 4-2 p76

20. Suggested Problems HW Set 2: 4.1, 4.4, 4.7-4.15 (odd) HW Set 3:4.17, 4.20, 4.23, 4.31, 4.35