1. Mass Percent of Oxygen in Potassium Chlorate

2. ChemistryName________________ Experiment # ______Section_____Date_____ Mass Percent of OxygenName(s) of Lab Partner(s) In Potassium Chlorate

3. Objective  To calculate the mass percent of oxygen in potassium chlorate

4. Procedure 1.Add a small amount of catalyst to a test tube 2.Record the mass of the test tube and catalyst 3.Put 2 scoops of KClO3 in test tube and mass again and mix 4.Heat the test tube with a burner until no more oxygen is seen

5. Procedure, con 5.Continue to heat another 2-3 minutes 6.Record your observations- allow to cool 7.Mass the test tube and products 8.Calculate the percent oxygen in potassium chlorate

6. Data  Mass of test tube and catalyst___  Mass of test tube, catalyst and KClO3___  Mass of test tube and products___  Observations (you must make)

7. Calculations  Percent of oxygen in KClO3 (skip 6 lines)

8.  Actual percent of oxygen in KClO 3 (skip 6 lines)  Percent error  Percent error = % in your gum – actual % X 100 = % actual %

9. Conclusion  The mass percent of oxygen in potassium chlorate according to my lab was ________. The actual value using the gram formula weight is ___________. My percent error is _________. Reasons for error include… (list 2)