1. (2 pt) Assign each of the following molecules to one of the major classes of biomolecules: CH, OH CH NM OM ON OH H OH H H HN 2. (2 pts) The H-O-H bond angle in the perfectly tetrahedral CH molecule is 109. Explain why the H-O-H bond angle in water is only about 104.5. H HAH H H H CH metre HO, water 3. (1 pt) Ethanol can act both as a H-bond donor and as a H-bond acceptor. What is the maximal number of H-bonds a single molecule of methanol can form with surrounding water molecules? a) 1 b) 2 c) 3 d) 4 e) 5 4. (2 pts) Explain why water has an unusually high heat capacity. Give an example of a molecule without an OH group that would be expected to have an unusually high heat capacity. 2