Which of the following pairs can be used to prepare a buffer? (select all that can apply)

a. HCl/NaCl
b. HF/KF
c. NH3/NH4Cl
d. HNO3/HNO2
e. NaNO2/HNO3

can you also please explain how they form a buffer? thank you

1 answer

Buffers are solutions contg a weak acid and its salt or a weak base and its salt OR something that can form a weak acid/base and salt.
b. Has weak acid,HF, and salt KF.
c. Has weak base, NH3, and salt, NH4Cl.
e. Has NaNO2 which is the salt of a weak acid and it contains HNO3 which can form a weak acid, HNO2, from the NaNO2 salt.