Consider the titration of a 35.0-mL sample of 0.175 M HBr with 0.200 M KOH. Determine each quantity. a. the initial pH

Verified step by step guidance

1. Identify the nature of the solution before any titrant is added. HBr is a strong acid, so it will completely dissociate in water.
2. Write the dissociation equation for HBr: \[ \text{HBr} \rightarrow \text{H}^+ + \text{Br}^- \]
3. Calculate the concentration of \( \text{H}^+ \) ions in the solution. Since HBr is a strong acid, the concentration of \( \text{H}^+ \) ions is equal to the concentration of HBr, which is 0.175 M.
4. Use the formula for pH: \[ \text{pH} = -\log[\text{H}^+] \] to find the initial pH of the solution.
5. Substitute the concentration of \( \text{H}^+ \) into the pH formula to determine the initial pH.

Key Concepts

Strong Acids and Bases

Strong acids, like HBr, completely dissociate in water, releasing H+ ions, while strong bases, such as KOH, fully dissociate to produce OH- ions. This complete dissociation is crucial for calculating pH and determining the behavior of the solution during titration.

pH Calculation

pH is a measure of the hydrogen ion concentration in a solution, calculated using the formula pH = -log[H+]. For strong acids, the initial pH can be directly determined from the concentration of the acid, as it fully dissociates, making it straightforward to find the initial pH before any titration occurs.

Titration Process

Titration is a technique used to determine the concentration of a solution by reacting it with a solution of known concentration. In this case, the titration of HBr with KOH will involve neutralization, where the pH changes as the base is added, allowing for the calculation of the initial pH before any KOH is introduced.