Lycoming College                                          Quiz 10                                                Write name on back

Chem 110, 2002                                                                                                                     upper right


1.      Write a plausible Lewis structure for NH2OH.








2.      In the NH2OH structure above, which bond is the most polar and what is the direction of the polarity?

(i.e., assign + and - to your choice)



3.   Consider the following dot structure:



      a.   What is wrong with this structure?  __________________________


      b.   Draw a corrected structure in the space to the right, above.


4.   For the species below, draw another Lewis resonance structure (two are possible) AND assign formal charges to each structure.


5.   Use bond energies to estimate DHrxn for the following reaction:


            CH4    +    Br2           CH3Br    +     HBr


Bond energies (kJ/mol):


            C - H  (435)                 Br Br  (192)              C Br  (293)               H Br   (368)