Procedure:

Follow the instructions. Draw structures; include the proper name of the compound. Have your work checked by the instructor.

  1. Construct a model of CH4. Rotate the model and observe.
  2. What type of bonds are formed, single, double or triple?
  3. What is the geometry of the molecule?
  1. Replace one hydrogen with a chlorine atom.

How many CH3Cl models are possible?

  1. Construct a model of C2H6. Notice that there is free rotation about the bond between the carbon atoms. Arrange the model to minimize the repulsion of the hydrogen atoms and sketch the end view.
  1. Replace one hydrogen with a chlorine atom and explain why it does not matter where the chlorine is placed on the model.
  1. Replace two hydrogen atoms of C2H6 with two chlorine atoms. Name and draw all the possible dichloroethanes.
  1. Construct a model of C3H8. Again replace one hydrogen with one chlorine atom to produce as many chloropropanes as possible. Draw the different isomers, naming each using IUPAC nomenclature.
  1. Replace two hydrogen atoms on C3H8 with two chlorine atoms to make as many isomers as possible. Draw structures; name each.

Build the following molecules:

Names / Structural Drawing
Butane (both chain + branched)
2-methylbutane
Hexane (both chain + branched)
methylpropane
Water
Hydrogen sulfide
Carbon tetrachloride
Formula / Build and Draw Structures
CH3CH3
CH2CH2
C6H12
CH3OH
CH3CH2COCH2CH3
CH3COCH3

Structural Organic Chemistry – Modeling Saturated Hydrocarbons

The purpose of this lab is to gain further familiarity with the three-dimensional structure of organic molecules and their isomers. Atoms are represented by balls of various colors. Molecular models are constructed by connecting the appropriately colored “atoms” with “covalent bonds”, represented by stiff and flexible connectors.

Different colored balls are used to symbolize the various elements. The following are fairly standard. If your modeling kit includes a color scheme, use it. The colors are arbitrary. Your kit will tell you which color is for which atom.

The number of drilled holes in each ball corresponds to the number of covalent bonds ordinarily formed by that particular element; the placement of the holes determines the angular orientation direction of the bond.