Final answer:
Use an ICE table to calculate equilibrium concentrations of reactants and products in chemical reactions, whereas the Henderson-Hasselbalch equation is for determining the pH of buffer solutions.
Step-by-step explanation:
Whether to use an ICE table or the Henderson-Hasselbalch equation depends on the problem at hand. An ICE table, which stands for Initial, Change, and Equilibrium, is used to track the changes in concentrations of reactants and products over the course of a reaction to determine the equilibrium concentrations. It is particularly useful in situations where the initial concentrations of reactants and products are known, and the reaction doesn't involve a buffer system.
On the other hand, the Henderson-Hasselbalch equation is specifically used to calculate the pH of buffer solutions. It relates the pH of a solution to the pKa of the acid and the concentrations of the acid and its conjugate base in solution. It's applicable when dealing with weak acid-base conjugate pairs in a buffer.
Therefore, if you are calculating the pH of a buffer solution, you would use the Henderson-Hasselbalch equation. If you need to find out equilibrium concentrations for a reaction, an ICE table is the appropriate tool.