Sodium nitride (NaNO2) is often used as a preservative for meats.

a) Knowing that the Ka of nitrous acid (HNO2) is 4.52 x 10^-4, find [OH-], [H3O+] and the pH of a solution of sodium nitride (NaNO2 ) 0.150 M. (Reminder: the nitride ion, NO2-, is the conjugate base of nitrous acid)

Answers:

[OH-]:

[H3O+]:

pH:

b) What mass of sodium nitrite (NaNO2) must be added to 100.0 mL of nitrous acid (HNO2) 0.150 M in order to prepare a buffer solution with a pH of 3.50?

mass of NaNO2: ________g