Answer Happy

~ 4.13 The epilimnion of your backyard pond has a pH = 7.0 and alkalinity ~ 10-3M. a. Assuming that the carbonate system dominates the chemistry of your pond, calculate the concentrations of all species. Is your pond at equi- librium with the atmosphere? Explain. b. You just washed the bricks of your house walls with HCl. How much acid can you add to your pond before changing the pH by more than 0.2 units (get an approximate answer by considering the buffering capacity). c. The hypolimnion of your pond is anoxic. Its composition is derived from that of the epilimnion by reducing 3 x 10-4 M of SO2 to H2S. What are the alkalinity, the pH, and the concentrations of all species in the hypolimnion? d. In the fall the epilimnion (1 m depth) and the hypolimnion (2 m depth) mix with minimal gas exchange. What is the composition (Alk, pH, concentrations) of the resulting water? e. What would the composition of the mixed water be if you forced mixing by bubbling air at the bottom of the pond (assume gas exchange, not oxidation)