Emotional Freedom

Chemistry I Chapter 8 Review Problems
Part I
Using the factor label method, neatly and clearly show all work. Answers are to include the unit, be in correct number of significant figures. If the answers are less than 1.0 or greater than 10, they are to be written in and be in correct scientific notation. Box your final answer.

Mass/Mole Problems

1. Determine the molar masses of the following compounds: a. dinitrogen pentoxide c. sodium carbonate

b. ammonium phosphate

2. Calculate the number of atoms in 20.0 grams of calcium. Road map: grams ( mols( atoms

20.0 g Ca x 1 mol Ca x 6.02 x 1023 atoms Ca 1 40.01 g Ca 1 mol Ca atoms

3. What is the mass of 6.20 moles of potassium iodide? Mol( grams

4. How many moles are contained in 84.2g of potassium sulfate?

5. Calculate the number of molecules in 3.34 moles of carbon dioxide.

6. What is the mass of 3.01 x 1023 atoms of sulfur?

7. What is the mass of 2.41 x 1024 molecules of water?

8. What is the formula mass (molar mass) of ammonium nitrate?

9. How many moles are in 56.2 grams of bromine gas?

10. What is the mass of 2.67 moles of sulfuric acid?

11. What is the mass of 3.5 moles of sodium sulfide?

12. Calculate the mass of 0.354 moles of ammonia, NH3.

13. Calculate the mass of 3.54 moles of sodium chloride.

14. Calculate the number of molecules of H2S in 68.0 g of hydrogen sulfate.

15. How many moles are found in 50.0 g of calcium citrate?

16. Determine the mass of 1.20 x 1024 moles of carbon dioxide.

Percent Composition

17. Determine the percent composition for each element in the following compounds: a. calcium carbonate e. strontium chloride

b. phosphoric acid (hydrogen phosphate) f. lead (II)