Last modified: Wed 02/10/2016 11:51:51 am BCE

Oklahoma State University

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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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Covalent bonding is defined as the sharing of electrons between atoms. The sharing occurs because, in very simple terms, atomic orbitals on the atoms that form the covalent bond, are overlapping.

For example, in the molecule HF , the electron configuration for H is 1s1, and for fluorine the electron configuration is 1s22s22p5 each need an electron to complete their outer most shells. The video shows a H atom approaching the F atom to form a covalent bond. The covalent bond is formed when the 1s orbital on H overlaps with a 2p orbital on F.

 

 

1. For each of the following cases indicate the atomic orbitals on each atom that must overlap to form the covalent bonds.

 

 

molecule

element

atomic orbital

element

atomic orbital

example

 

HF

H

1s

F

2p

a)

 

H2

H

H

b)

 

F2

F

F

c)

H2O

H

O

d)

NH3

H

N

e)

 

CH4

H

C

2. What is the bond angle for each of the following compounds? (Check out the angles using Jmol. In the dropdown menu list near the top of the page select the compound and measure the appropriate bond angle by double clicking on the first atom, dragging the cursor to the second atom and single clicking, and then dragging and double clicking on the third atom.)

a) H-O-H bond angle in H2O? degrees

b) H-N-H bond angle in NH3? degrees

c) H-C-H bond angle in CH4? degrees

3. Consider the following molecules: H2CO, C2H4, and HCOOH. (Draw Lewis structures. Here is a link to the VSEPR table.) Complete the following table:

Formula

# of Bonding domains on the Carbon atom

# of lone pairs of electrons on the Carbon atom

Molecular Geometry on the Carbon atom

H2CO


C2H4


HCOOH


 

4. What connection/rule would you make about the molecular geometry on the carbon atom(s) and the number of bonding domains and nonbonding domains in these three molecules?

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?