Question

Consider the following equilibrium:

HF + H2O(l) H3O+ + F -
Under what circumstances will this system behave as a buffer?
A.
when [F -] is equal to Ka
B.
when [F -] is equal to [HF]
C.
when [F -] is equal to [H2O]
D.
when [F -] is equal to [H3O]

Answer 1

see explanataion

Step-by-step explanation:

Buffer solutions are defined as solutions containing a weak electrolyte (wk acid or wk base) and the salt of the weak electrolyte.

Given HF(aq) + H₂O(l) ⇄ H₃O(l) + F⁻, a buffer solution would result from a solution composition when [F -] is equal to [HF]. Such is commonly referred to as a 50/50 buffer as the acid and salt are in equal concentrations. However, a buffer solution still will exist even if the concentrations of acid and salt are not equal. The presence of the weak acid or weak base and the salt of the electrolytes is the only requirement.

Answer 2

B.

Step-by-step explanation:

Buffer has equal concentrations of A- and HA.

B. when [F -] is equal to [HF]