Molecule Shape Lab

Background Information: Covalent bonding is the most common type of bond. When two or more atoms share a pair of electrons a covalent bond is formed. A polar covalent bond is formed when atoms have different electronegativities. The electrons are attracted to the atom with the higher electronegativity. On the other hand, if both atoms have the same electronegativity the bond is then nonpolar covalent. In the experiment we will be conducting, we will be constructing models of molecules and deciphering their polarity based on their shape.

Materials: 1 Model Kit including 5 carbon atoms, 15 regular bonding shafts, 5 bendy bonding shafts, 7 oxygen atoms, 3 nitrogen atoms, 8 hydrogen atoms, 6 fluorine atoms, also we had reference work sheets of the geometry of molecules.

Procedure: Draw the lewis structure for the sixteen elements then make 3D models of each. after constructing the 3D models we were to draw 2D pictures on the worksheet. after all the diagrams were made and drawn out we had to write out the molecular geometry, bond angle, polarity and whether or not it was a resonance structure.

H2O



Linear
90 degree bond angle
polar
















C3H8




Tetrahedron
109.5 degree bond angle
polar















CH4



tetrahedron
109.5 degree bond angle
nonpolar


















BF3




trigonalplaner
120 degree bond angle
nonpolar














SF6



Octet
90 degree bond angle
polar


















Conclusion: We found that only one of the molecules was a resonance structure and that all the molecules followed the octet rule.
The models and the lewis structures don't necessarily look alike.