1 It is believed that the substances are among the following copper compounds: CuF2,_CuCI2* 2H2O, CuI2, Cu(C2H3O2)2 * H2O, CuCI2, CuBr2, CuSO4 * 5H2O, Cu(CN)2

2. Each of the unknowns has a unique molar mass. What information do you need to determine a molar mass?

3. Your unknown is a solid but you probably will want to make measurements in solution. What do you need to know/consider when making up a solution of your unknown?

4. When making up an unknown solution for absorption measurements, a good plain is to make up a solution that is rather on the concentrated side, measure its absorbance and compare it to the absorbance range of your standard curve. If it is higher than the absorption range in the standard curve, than you can dilute until you measure a more reasonable absorbance. Just remember-keep careful track of your dilutions- you will have to use those factors in your final data analysis!

5. You've already created concentration vs. absorbance curves in Part A of this lab that could be used as a standard curve for Cu 2+. Which curve would be most useful considering you do not know the identity of your unknown? (Hint: Which curve is NOT compound dependent?)

6. Additional Calculations can be done to find the moles of copper in the solution. All the possible copper compounds contain only one atom of copper per formula unit