Chapter 2 Objectives (Review)

1. Define element and compound.

2. State four elements essential to life that make up 96% of living matter.

3. Describe the structure of an atom.

4. Define and distinguish among atomic number, mass number, atomic weight and valence.

5. Given the atomic number and mass number of an atom, determine the number of neutrons.

6. Explain why radioisotopes are important to biologists.

7. Explain how electron configuration influences the chemical behavior of an atom.

8. Explain the octet rule and predict how many bonds an atom might form.

9. Explain why the noble gases are so unreactive.

10. Define electronegativity and explain how it influences the formation of chemical bonds.

11. Distinguish among nonpolar covalent, polar covalent and ionic bonds.

12. Describe the formation of a hydrogen bond and explain how it differs from a covalent or ionic bond.

13. Explain why weak bonds are important to living organisms.

14. Describe how the relative concentrations of reactants and products affect a chemical reaction.

15. Describe the chemical conditions on early Earth and explain how they were different from today.

Chapter 3 Objectives

1. Describe how water contributes to the fitness of the environment to support life.

2. Describe the structure and geometry of a water molecule, and explain what properties emerge as a result of this structure.

3. Explain the relationship between the polar nature of water and its ability to form hydrogen bonds.

4. List five characteristics of water that are emergent properties resulting from hydrogen bonding.

5. Describe the biological significance of the cohesiveness of water.

6. Distinguish between heat and temperature.

7. Explain how water's high specific heat, high heat of vaporization and expansion upon freezing affect both aquatic and terrestrial ecosystems.

8. Explain how the polarity of the water molecule makes it a versatile solvent.

9. Define molarity and list some advantages of measuring substances in moles.

10. Write the equation for the dissociation of water, and explain what is actually transferred from one molecule to another.

11. Explain the basis for the pH scale.

12. Explain how acids and bases directly or indirectly affect the hydrogen ion concentration of a solution.

13. Using the bicarbonate buffer system as an example, explain how buffers work.