Determine the ph change when 0090 mol koh is added to 100 l

Question

1. A buffer solution contains 0.477 M NH₄Cl and 0.356 M NH₃ (ammonia). Determine the pH change when 0.073mol NaOH is added to 1.00 L of the buffer.

pH after addition - pH before addition = pH change =

2. Determine the pH change when 0.090 mol KOH is added to 1.00 L of a buffer solution that is 0.384 M in HCN and 0.385 M in CN^-.

pH after addition - pH before addition = pH change =

3. How many moles of potassium hydroxide would have to be added to 250 mL of a 0.383 M hypochlorous acidsolution, in order to prepare an buffer with a pH of 7.270?________moles

4. An aqueous solution contains 0.485 M hydrocyanic acid.

How many mL of 0.347 M potassium hydroxide would have to be added to 225 mL of this solution in order to prepare an buffer with a pH of 9.090?

3. How many moles of potassium hydroxide would have to be added to 250 mL of a 0.383 M hypochlorous acidsolution, in order to prepare  buffer with a pH of 7.270?