What is the pH of a 0.200M solution for HBrO?

Ka = 2.8 x 10^-9

See above.

To determine the pH of a solution, you will need to consider the concentration of the hydrogen ions (H+) or hydroxide ions (OH-) present. In the case of a weak acid like HBrO, we can use the equilibrium expression (Ka) to determine the concentration of H+.

The equilibrium expression for an acid dissociation reaction is given by:

Ka = [H+][BrO-] / [HBrO]

Given that the initial concentration of HBrO is 0.200 M, and assuming x is the concentration of H+ (which dissociates to form H3O+ in water):

Ka = [x][0.200-x] / [0.200]

Simplifying the equation, we have:

Ka = x(0.200 - x) / 0.200

Since x is much smaller than 0.200, we can make the approximation that 0.200 - x ≈ 0.200. Thus:

Ka ≈ x(0.200) / 0.200 (simplifying further)

Now we can solve for x:

2.8 x 10^-9 = x(0.200) / 0.200

2.8 x 10^-9 = x

Now that we know the concentration of H+, we can calculate the pH using the formula:

pH = -log [H+]

pH = -log (2.8 x 10^-9)

Using a calculator, we find that the pH is approximately 8.554.

Note: It's important to remember that this is an approximation since we made the assumption that 0.200 - x ≈ 0.200.