1 calculate the ph value of a solution having a

Question

1. Calculate the pH value of a solution having a concentration of H⁺(hydrogen ion) of 5.35E-09 M at 25°C ? (Include 2 decimal points).

pH =??

2. The pK_a of the ammonium ion is 9.25. NH₃/NH₄⁺ is a good buffer:

a.  Between pH 10.25 and 11.25.  

b. Between pH 7.25 and 8.25.  

c. At pH values less than 7.0.  

d. At pH 4.63.  

e. Between pH 8.25 and 10.25.