VSEPR Lab
Molecular Structure or "The Shape Molecules are In"
Directions: Make a copy of this document and change the file name to “your last name,
VSEPR Lab.” Place the document in the Google folder with your name on it. Follow each instruction to build molecular models and answer the following questions. Make sure your notes, comments, and answers are in a different text color. When you have finished with the lab questions attach a 12 page conclusion that summarizes and explains the main points of the lab. 1. After you have washed your hands, obtain your "atom" supply from Dr. Winston. Select one atom from your atom supply. Using four toothpicks, place them as far apart from each other around the atom. Remember, electrons have the same charge (negative) so it is their desire to be as far away from each other as possible. 2. The toothpicks represent single electrons as in carbon (four valence electrons) or if hydrogens come along and attach to each of the four toothpicks, then the toothpicks represent an electron pair shared between each hydrogen and carbon. 3. If you placed the toothpicks as far apart as they can be from each other in 3D you will be able to stand the atom on the table with no more than 3 toothpicks touching the table at one time. Try it, and if you can't readjust the toothpicks so that it can stand alone. Hint: the arrangement of electrons (toothpicks) should demonstrate threedimensional symmetry; i.e. it should look the same no matter how you rotate it. 4. The name of this arrangement is_tetrahedral_. Use a protractor to measure the angle between each electrons (toothpicks) to the correct number of significant digits. How many different angles can be measured? 6
Measure the angles and determine the average.114.4° If you had constructed the perfect
Molecule what should the angle between any two electrons be? 109.5° 5. Try to rearrange your model to reflect the correct angle between each electron. 6. Use
Directions: Make a copy of this document and change the file name to “your last name,
VSEPR Lab.” Place the document in the Google folder with your name on it. Follow each instruction to build molecular models and answer the following questions. Make sure your notes, comments, and answers are in a different text color. When you have finished with the lab questions attach a 12 page conclusion that summarizes and explains the main points of the lab. 1. After you have washed your hands, obtain your "atom" supply from Dr. Winston. Select one atom from your atom supply. Using four toothpicks, place them as far apart from each other around the atom. Remember, electrons have the same charge (negative) so it is their desire to be as far away from each other as possible. 2. The toothpicks represent single electrons as in carbon (four valence electrons) or if hydrogens come along and attach to each of the four toothpicks, then the toothpicks represent an electron pair shared between each hydrogen and carbon. 3. If you placed the toothpicks as far apart as they can be from each other in 3D you will be able to stand the atom on the table with no more than 3 toothpicks touching the table at one time. Try it, and if you can't readjust the toothpicks so that it can stand alone. Hint: the arrangement of electrons (toothpicks) should demonstrate threedimensional symmetry; i.e. it should look the same no matter how you rotate it. 4. The name of this arrangement is_tetrahedral_. Use a protractor to measure the angle between each electrons (toothpicks) to the correct number of significant digits. How many different angles can be measured? 6
Measure the angles and determine the average.114.4° If you had constructed the perfect
Molecule what should the angle between any two electrons be? 109.5° 5. Try to rearrange your model to reflect the correct angle between each electron. 6. Use