Objectives

You have completed this lesson when you can:

1. Define and distinguish between fact, observation, inference, hypothesis, scientific law, theory, and model.

2. Describe the scientific method and list four criteria for judging theories.

3. Describe and distinguish between these categories of materials: mixtures, solutions, pure substances, compounds and elements.

4. Explain what is meant by the Law of Constant Composition, as well as stating it, recognizing it, or identifying examples of it. Use it to distinguish between compounds and other classes of materials.

5. Locate a given element on the periodic table, associate its symbol with its name, and determine the period and group it is in.

6. Use the names of compounds to determine what elements are present in them.

7. State and recognize the basic points of Dalton's Atomic Theory. Describe Dalton's model of atoms.

8. Define "mole" using the definition based on the formula mass of a substance

9. Convert from grams to moles and from moles to grams for any substance

10. Define "compound" and "molecule" and distinguish between them.

11. State Avogadro's Law and explain how it relates to molecules and compounds and elements. Describe the differences between Avogadro's "molecule" and Dalton's "compound atom."

12. Express the composition of chemicals using formulas. Given the number of each kind of atom in a compound, write its formula, and vice versa.

13. Define and distinguish between empirical, molecular, and structural formulas.

14. Define and calculate formula masses (including molecular masses) given the formula of a chemical using the periodic table.

15. Determine the percent composition by mass of a compound from its formula using the periodic table.

16. Calculate the percent composition by mass of a compound or solution given the masses of its components.

17. Determine the empirical formula of a compound using absolute composition or percent composition data.

18. Experimentally determine the molecular weight of gases.

19. Determine the molecular formula of a compound given its empirical formula and its molecular mass.

Assignments:

• Sapling Lesson 2 Homework

• Lesson 2 Prelab

• Lesson 2 Lab Assignment (p. 7-8)

• Lesson 2 Moodle Forum (hybrid only)