4: Equilibrium and Activity
- Page ID
- 401470
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- 4.1: Solving Equilibrium Problems
- In this section we will learn how to set‐up and solve equilibrium problems.
- 4.2: Buffer Solutions
- Adding as little as 0.1 mL of concentrated HCl to a liter of \(\text{H}_2\text{O}\) shifts the pH from 7.0 to 3.0. Adding the same amount of HCl to a liter of a solution that 0.1 M in acetic acid and 0.1 M in sodium acetate, however, results in a negligible change in pH. Why do these two solutions respond so differently to the addition of HCl? A mixture of acetic acid and sodium acetate is one example of an acid–base buffer.
- 4.3: Activity Effects
- Careful measurements on the metal–ligand complex \(\text{Fe(SCN)}^{2+}\) suggest its stability, and thus its equilibrium constant, decreases in the presence of inert ions. Understanding why this is so is critical to developing a complete understanding of equilibrium chemistry.