Correct Answer - 3.67×10-4
∧
∘
m(HCOOH)
=∧
∘
(H⊕)
+∧
∘
(HCOOc-)
=349.6+54.6Scm2mol-1
=404.2Scm2mol-1
∧
∘
m
=46.1Scm2mol-1( Given )
∴α=
∧
∘
m
∧
∘
m
=
46.1
404.2
=0.114
HCOOH ⇔ HCOOc- + H⊕
Initial conc c molL-1 - -
Conc at Eq c(1-α) calpha calpha
Ka=
calpha.calpha
c(1-α)
=
cα2
1-α
=
0.025×(0.114)2
1-0.114
=3.67×10-4