Building Small Molecules - III
Total time: 5 minutes
Task A: Convert Methane, CH4 to ethane CH3CH3
- Open the "methane" file you created
in the last lesson and change the name
by selecting File|Save As . Name the new file "ethane".
-
Select the Atom icon
.
-
Select the arrow button in the
element type box
and select carbon.
Make sure the hybridization is sp3
.
-
Click in the center of the carbon atom in the methane molecule
and drag away from the atom
.
-
When you release the mouse key a second carbon atom appears
.
- Click on the
select tool
and click in the
workspace (not on any atoms or bonds) to select the entire molecule.
- To fix the geometry of the ethane molecule, select
Beautify|Comprehensive from the menu bar.
The correct number of hydrogen atoms will also be added, as well.

- To save your finished molecule select File|Save and save
it as "ethane".
Task B: Convert Ethane CH3CH3
to Butane CH3CH2CH2CH3
- Keep the workspace with the ethane molecule open, but change the name by
selecting File|Save As . Name the new file "butane".
-
Select the Atom icon
. Make sure that carbon shows in the
element type box
and select carbon.
Make sure the hybridization is sp3
.
-
Click in the center of a carbon atom in the ethane molecule
and drag to add a third carbon atom. Repeat this step to add a fourth carbon
atom.

- Click on the
select tool
and click in the
workspace (not on any atoms or bonds) to select the entire molecule.
- To fix the geometry of the butane molecule, select
Beautify|Comprehensive
from the menu bar. The correct number of hydrogen atoms will also be added, as
well.

- To save your finished molecule select File|Save and save
it as "butane".
This is the last lesson in this module on building simple molecules.
Go on to the next module: building
inorganic molecules and ions.