what is the pH of .28 M HNO3 (aq) at 25 degree celsius? (Kw = 1.0 x 10 ^-14)

HNO3 is a strong acid; it is ionized 100%. Therefore, (HNO3) = (H^+) = 0.28 M. Convert to pH.

To find the pH of a solution, you first need to calculate the concentration of hydronium ions ([H3O+]) in the solution. In the case of a strong acid like HNO3, it dissociates completely in water, producing H3O+ ions.

The balanced equation for the dissociation of nitric acid (HNO3) is:
HNO3 → H+ + NO3-

Since the initial concentration of HNO3 is 0.28 M, we can assume that the concentration of [H3O+] will be the same.

Therefore, the concentration of H3O+ ions is 0.28 M.

Next, you can find the pH using the equation:
pH = -log[H3O+]

Substituting the value of [H3O+] into the equation:
pH = -log(0.28)

Calculating this using a scientific calculator:
pH ≈ 0.55

Therefore, the pH of the 0.28 M HNO3 solution at 25 degrees Celsius is approximately 0.55.