Chapter 9 Mass Relationships Lab Report Sheet

Chapter 9 Mass relationships lab report sheet Problem: Can you come up the correct mole ratio for copper II chloride in your final product? These are your reactions in this experiment:

CuCl2 2H20  CuCl2 + 2H20 2Al + 3CuCl2  3Cu + 2AlCl3

Prelab 1.What kind of reaction would start with a single reactant and involve an apparent decrease in mass?

2.Why must you avoid using the stirring rod to break up the solid while it is in the filter?

3.Why is it an error to weigh the beaker for day one before adding the masking tape?

4.When you break up the product, you place the rod on your desk in between using it-why can this be a source of human error?

Data Table 1.Mass of labeled beaker______2.Mass of calcium chloride before mixing it______3.Mass of beaker and sample before heating it______4.Mass of beaker and sample after heating it______5.Mass of filter paper______6.Mass of filter paper and dried product______7.Mass of dried product remaining______

Observations 1.During heating of the calcium chloride:

2.While adding water to the dried brown substance:

3.When the aluminum was added to the blue solution: Analysis 1B.mass of original sample (#2)______2B.mass lost (#3-#4)______3B.mass solid after heating(#4-#1)______4B.Mass of final product (#6-#5)______

Use the following formula for the next set of questions:

CuCl2 2H20  CuCl2 + 2H20 Let’s find out if your data is good enough to come up with the correct mole ratio to make CuCl2

5B.How many moles of copper did you recover? (turn the g of the final product to moles)

6B.How many moles of aluminum must have reacted? (turn the moles of copper into moles aluminum using the coefficients of the balance equation)

7B.What mass of chlorine was in the final product? mass solid after heating(#3B)-mass copper recovered(#4B)

8B. How many moles of chlorine were in the compound? (turn the mass of chlorine into moles)

9B. What is the mole ratio of chlorine to copper?

Chlorine moles Copper moles

10. The ratio from #9B represents the number of chlorine atoms per copper atoms in the compound-what is the correct formula for copper(I or II chloride? LET’S FIND OUT HOW GOOD YOUR DATA IS!! 11.Where did the mass loss come from after heating?

12.List three examples of chemical change throughout the experiment: