Question

Which of the following can be classified as buffer solutions?
a) 0.25 M HBr + 0.25 M HOBr
b) 0.15 M HClO4 + 0.2 M RbOH
c) 0.5 M HOCl + 0.35 M KOCl
d) 0.7 M KOH + 0.7 M HONH2
e) 0.85 M H2NNH2 + 0.6 M H2NNH3NO3

Answer 1

buffer is a mixture of Weak acid and its conjugate base or

Weak base and its conjugate acid

a) 0.25 M HBr + 0.25 M HOBr

HBr is strong acid. a strong acid can not form buffer
b) 0.15 M HClO4 + 0.2 M RbOH

HClO4 is also a strong acid. so can not form buffer

c) 0.5 M HOCl + 0.35 M KOCl

HOCl is weak acid and KOCl is conjugate base . so it act as buffer

d) 0.7 M KOH + 0.7 M HONH2

KOH is strong base. so can not form buffer
e) 0.85 M H2NNH2 + 0.6 M H2NNH3NO3

NH2NH2 is a weak base and NH2NH3NO3 is conjugate acid .

so act as Buffer