Last modified: Wed 12/31/1969 06:00:00 pm
ACA

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Answer all of the questions below. If you do not know an answer enter CNA. However, it will help me the most if you answer each question with your best intuition/idea about what would be a reasonable answer.


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Laboratory Section:

1. A possible Lewis structure for ClO2- is

What is the formal charge on Cl in this Lewis structure? (NOTE: The formal charge on an atom is calculated FC(atom) = # valence electrons (atom) - 1/2*#bonding electrons (atom) - #nonbonding electrons (atoms).)

2. What is the formal charge on O in this Lewis structure? (NOTE: The formal charge on an atom is calculated FC(atom) = # valence electrons (atom) - 1/2*#bonding electrons (atom) - #nonbonding electrons (atoms).)

3. Using the bond energies in the table

Bond

Bond Energy (kJ mol-1)

H-C

413
Cl-Cl

239
C-Cl

339
H-Cl

427

estimate H˚rxn for the reaction;

CH4(g) + 2Cl2(g) ---> CH2Cl2(g) + 2HCl(g)

Hint: Be sure to draw the Lewis structures for all molecules in the chemical equation.

kJ mol-1

4. Complete the following table. Here is a table of molecular geometries;

Formula

# of Bonding domains (CA)

# of nonbonding domains(CA)

Molecular Geometry

Bond Angle (TA-CA-TA)

NF3

CH2F2

ONCl

ICl4-

(Note: TA is terminal atom. CA is central atom.)

5. Is there anything about the questions that you feel you do not understand? List your concerns/questions.

6. If there is one question you would like to have answered in lecture, what would that question be?