pH Calculations October 21, 1997

1. a) [OH^-] = 2.5x10^-7 M ; pH = ________________

b) [OH^-] = 2.5x10^-7 M ; pOH = ________________

c) [HNO3] = 0.0035 M; pH = ________________

2. pOH = 4.87 pH= ______.

pH = 5.6 [H⁺] = ___________.

 [OH^-] = .00087 [H⁺] = ___________.

3. 0.25 mL of 0.010 M HCl mixed with 100 mL of H₂O; pH = ________.

4. H₂SO₄ is an Arrhenius acid. What reaction equation describes this fact?

5. H₂SO₄ is an Bronstead acid. What is the conjugate base of H₂SO₄ ?

6. Write the net ionic reaction between the Arrhenius acid H₂SO₄ and the Arrhenius base NaOH?

7. A solution contains 0.20 M HF (Ka= 6.8x10^-4 ).

a) What is the reaction equation involved in determining the pH of the solution?

b) If the [H⁺] = x, what are the [F-] and [HF] in terms of x.

(one answer [HF] =0.20 -x)

c) What is the equilibrium expresseion for the reaction in a. 

d) Calculate the pH of the solution.