Chem B: Lab Practical Skills Check

(You should be able to do the work on this page before beginning the lab practical)

1. You need 1000 ml of 3M PbI2.  Explain the process of making this solution.

2. You need to work with 15ml of this solution.

1. How do you collect this sample?

2. How do you determine the mass of this sample?  (be sure to include the tools you will use in your answer)

3. Calculate the number of moles in your 1000ml sample

4. Calculate how many g of solute are in your 1000ml sample

5. Calculate the number of moles in your 15 ml sample

6. Calculate how many g of solute are in your 15 ml sample

3. You will use your solution to perform the following (unbalanced) reaction:

KHCO3 + PbI2 --> KI  +  CO2  +  H2O  +  PbO

Use what you know about your 15ml solution and the given reaction to determine:

7. Name each chemical name

8. Balance the equation

4. Starting with you 15 ml solution of PbI2 (use stoich and mole ratios)

1. How many moles of KHCO3 will you need to use up all of the PbI2?

2. How many grams of KHCO3 will you need to use up all of the PBI2

3. How many moles of KI will be produced?

4. How many grams of KI will be produced?

5. How many moles of CO2 will be produced?

6. How many grams of CO2 will be produced?

7. How many moles of H2O will be produced?

8. How many grams of H2O will be produced?

9. How many moles of PbO will be produced?

10. How many grams of PbO will be produced?

5. Suppose, you perform the reaction given above. You can calculate the amount of CO2 produced with stoich, but how would you determine the mass of the CO2 experimentally?  In case you forgot, CO2 is a gas.

6. How would you calculate the percent error of your actual  CO2 amount (obtained in the experiment) compared with the calculated CO2 amount (from your stoich problem)?