Chem 31B is the second course in this two-quarter sequence, therefore only students who have completed Chem 31A may enroll in CHEM 31B. As with CHEM 31A, students will continue to engage in group problem-solving activities throughout class and participate in weekly laboratory activities. Labs and write-ups will allow students to more deeply explore and observe the different facets of chemical reactivity, including rates (kinetics), energetics (thermodynamics), and reversibility (equilibrium) of reactions. Through experimentation and discussion, students will determine what forces influence the rate of chemical reactions and learn how this can be applied to enzyme reactivity. Students will quantify chemical concentrations during a reaction, and predict the direction in which a reaction will shift in order to achieve equilibrium, including solubility equilibria. They will use these methods to estimate the possible levels of lead and other toxic metals in drinking water. Special emphasis will be placed on acid/base equilibria , allowing students to explore the role of buffers and antacids in our bodies, as well as ocean acidification and the impact on coral reefs. Students will then bring together concepts from both kinetics and equilibrium, in a deeper discussion of thermodynamics, to understand what ultimately influences the spontaneity of a reaction. Students will build a relationship between free energy, temperature, and equilibrium constants to be able to calculate the free energy of a reaction and understand how processes in our body are coupled to harness excess free energy to do useful work. Finally we will explore how we harness work from redox reactions, building both voltaic cells (i.e. batteries) and electrolytic cells in lab, and using reduction potentials to predict spontaneity and potential of a given reaction. We will look at the applications of redox chemistry in electric and fuel cell vehicles. The course's particular emphasis on understanding the driving forces of a reaction, especially the influence of thermodynamics versus kinetics, will prepare students for further study of predicting organic chemical reactivity and equilibria from structure in Chem 33.