1. What is an oxidation number?

2. List the guidelines for determining oxidation numbers.

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2.

3.

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7.

8.

3. Assign oxidation numbers to each atom in the following compounds or ions:

KClO₄

SO₃^2-

NF₃

CO₂

NO₃^-

NH₄Cl

4. Define the term formula mass.

5. Find the formula mass for each of the following:

Na₂SO₃ HClO₃

MnO₄^- C₂H₆O

6. What is the mass in grams of 3.04 mol of ammonia vapor, NH₃?

7. Calculate the mass of 0.257 mol of calcium nitrate, Ca(NO₃)₂.

8. How many moles are in 3.82 grams of sulfur (IV) oxide?

9. How many moles are there in 4.15 x 10^-3 g C₆H₁₂O₆?

10. What is percentage composition? Write the formula used to determine the percentage composition.

11. Calculate the percentage composition of sodium nitrate.

12. Calculate the percentage composition of silver (I) sulfate.

13. What is an empirical formula?

14. List the steps to determining an empirical formula.

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15. A compound is found to contain 63.52% iron and 36.48% sulfur. Find its empirical formula.

16. A 60.00 g sample of tetraethyllead, a gasoline additive, is foud to contain 38.43 g lead, 17.83 g carbon, and 3.74 g hydrogen. Find its empirical formula.

17. What information do you need in order to determine the molecular formula of a compound?

18. Determine the molecular formula of the compound with an empirical formula of CH and a formula mass of 78.110 amu.

19. Determine the molecular formula of a compound with an empirical formula of NH₂ and a formula mass of 32.06 amu.