Chemistry 401

Intermediate Inorganic Chemistry

University of Rhode Island

Fall 2000

Exam 3

1. The Drago-Wayland equation is designed for complex formation reactions, but can be used to determine the enthalpy of reaction for substitution and metathesis reactions by using the appropriate thermochemical cycle. Using the data from Table 5.4, estimate the enthalpy of the reaction ICl–NH3 + P(CH3)3 → ICl–P(CH3)3 + NH3. Hint: first find ΔHformation for each Lewis acid/base complex separately.

2. Use the Latimer diagram for Se in acidic solution (Appendix 2) to find the reduction potential for the reduction of SeO42– to Se. Write the balanced half-reaction.

3. Give the systematic names for the following complexes: K3[Fe(CN)6]; [Cr(NH3)6]Br3 Give the structures for the following compounds: sodium fac–trichlorotrifluorocobaltate(III); dicyano–η2–etheneplatinum(II).

4. Find the ligand field stabilization energy in terms of Dq for the following complexes: Cr(NH3)63+; Fe(NH3)62+; Cr(CN)63–; Zn(NH3)42+. Order the complexes from least stable to most stable.

5. Which of the following compounds is stable as judged by the effective atomic number rule? Ni(CO)4; V(CO)6; Mn(cp)2; Cu(NH3)2Cl2. For those that you predict to be unstable, what is a likely chemical reaction for the compound? cp = η5–C5H5

 

 

Answers