Procedural Questions (to answer these, you must read/watch information in the Procedures document)

1. What does it mean when the analysis is quantitative?

2. Research the formula for percent error and write it in your lab report for later use. Be sure to get it from a reputable source (not Yahoo answers, etc).

3. What does it mean when the analysis is qualitative?

4. How long should you rinse a spill on your skin?

5. a) What is the formula for nitric acid?
   b) What is the formula for silver nitrate?

6. Why would you do this for two separate samples in real life?

7. Why don’t you add the sample over the balance?

8. What is the difference in flame appearance/sound for high vs low temperature flames? How can you adjust the temperature on your burner?

9. State the Law of Conservation of Mass. The mass of your crucible, lid, and sample is decreasing. How can that be?

10. Do you need to heat a third time? Why or why not?




11.     

Questions

1. Was your average experimental mass percent of oxygen in potassium chlorate higher or lower than the theoretical value (circle one)? Higher Lower

Which of the following sources of error could be used to explain this discrepancy (circle one)?

1. The potassium chlorate sample was not heated strongly or long enough.

2. Some of the potassium chloride product splattered out of the crucible during the heating process.

Explain your choice. Your response should include an analysis of the calculations you performed with your raw data to obtain your experimental % of oxygen.

2. Suppose the stockroom made a mistake and gave you a mixture of potassium chlorate and potassium chlorite. Upon analysis of this mixture, would you obtain a larger or smaller mass percent of oxygen than you would for an equal mass of pure sample of potassium chlorate (circle one)?
   
   Larger Smaller

Explain your choice. Your response should include an analysis of the formulas of the compounds involved.

3. Show your calculations clearly. Suppose you are provided with a 36.55 g sample of potassium chlorate.

1. What mass of oxygen should theoretically be released upon heating?
   
   
   
   

2. What mass of potassium chloride residue should theoretically be left over after heating?

Transcribed Image Text:

Experimental Data (a) Mass of crucible + lid (b) Mass of crucible, lid + KCIO, (c) Mass of crucible, lid + residue after 1"heating (d) Mass of crucible, lid + residue after 2d heating (e) Mass of crucible, lid + residue after 3d heating Sample 1 Experimental Data (a) Mass of crucible + lid (b) Mass of crucible, lid + KCIO, (c) Mass of crucible, lid + residue after 1"heating (d) Mass of crucible, lid + residue after 2d heating (e) Mass of crucible, lid + residue after 3d heating Sample 1

Answer rating: 100% (QA)

Answer Was your average experimental mass ... View the full answer