Polaritry and Molecular shape lab w/ Lewis Dot structures

Objectives

• Construct models of molecules.


• Determine molecular shapes.


• Predict polarity of molecules.

Materials

• Molecular model kit.




• Black- Carbon, Nitrogen and Silicon.


• White- Hydrogen


• Red- Oxygen


• Green straw- Covalent bond
  


• Green- Halogens
  


• White straw- Double bonds


• Pink- Iodine and Selenium


• Grey- Sulfur


• Blue- Boron
  

Procedure

1. Build a model for each of the molecules listed on the data table on the back of this page. (Remember that some atoms can form multiple bonds.)


2. Draw the three-dimensional structure of each molecule in Table 1. (Make a copy of Table 1 on your own paper) Use solid lines to represent bonds in the plane of the paper, dashed lines for bonds that point back from the plane of the paper, and wedged lines for bonds that point out from the plane of the paper toward the viewer.


3. Note the shape of each molecule in the third column of Table 1, the bond angles in, whether or not they will be polar, and whether or not they exhibit resonance structure.

Analysis

1. Water's shape causes it to be polar because the water molecule has a negative and positive end, which helps the molecule stick to itself.


2. Water's properties would be different if the molecules were different because, they wouldn't stick to each other as well.


3. The molecules that are water-soluble are:

Results:
See Shape Lab(Photos)



Conclusion:
Molecules polarity are determined by their shape, and electronegativity. The shape is determined by the number of different repelling groups.


See photos @:
http://lhschem56.blogspot.com/2010/02/lew-structure-shape-labphotos.html