Question 1: Hydrocarbons (12 points)

A. Draw the structural model for butane (using C and H). (6 points)

B. Draw the stick (or skeletal) model for 3-hexyne. (4 points)

C. The molecule below is trans-2-pentene. Draw a stereoisomer of this molecule. (2 points)

Question 2: Functional Groups (6 points)

A. Methanoic acid is the simplest carboxylic acid molecule. It has one carbon atom. Draw the structural model for methanoic acid (using C and H). (3 points)

B.Methanal is the simplest aldehyde, with one carbon atom. Draw the structural model for methanal (using C and H). (3 points)

Question 3: Biological Molecules (8 points)

A. How is a protein different from a polypeptide? (3 points)

B. The molecule shown below has three fatty-acid chains attached to it. 

      i. What type of biological macromolecule is this? (2 points)

      ii. State and explain whether this is a saturated or unsaturated molecule. (3 points)

Question 4: Biological Molecules (5 points)

A. Pepsin is an enzyme used by the human body to break down food in the stomach.

      i. Explain, in terms of a chemical reaction, how pepsin helps a person. (3 points)

      ii. What are the building blocks of the pepsin macromolecule? (2 points)