Explain Ostwald dilution law and Buffer solutions with types.
Answers
Answer:
Ostwald's dilution law relates the dissociation constant of the weak electrolyte with the degree of dissociation and the concentration of the weak electrolyte. Consider the dissociation equilibrium of CH
3
COOH which is a weak electrolyte in water.
CH
3
COOH⇌CH
3
COO
−
+H
+
K
a
=
[CH
3
COOH]
[CH
3
COO
−
][H
+
]
α=degree of dissociation of acetic acid.
∴K
a
=
(1−α)C
αC×αC
K
a
=
1−α
α
2
C
Ostwald's dilution law
If α is too small, K
a
=α
2
C
α
2
C=K
a
α
2
=
C
K
a
α=
C
K
a
[H
1
]=Cα
=C
C
K
a
=
C
K
a
C
2
=
K
a
C
∴[H
+
]=
K
a
C
K
a
=α
2
C−Ostwald's dilution law for weak acid.
K
b
=α
2
C−Ostwald's dilution law for weak base.
Explanation:
OSTWALD DILUTION LAW-
Ostwald's dilution law relates the dissociation constant of the weak electrolyte with the degree of dissociation and the concentration of the weak electrolyte. Consider the dissociation equilibrium of CH3COOH which is a weak electrolyte in water.
BUFFER SOLUTION AND ITS TYPES-
Buffers are solutions that resist a change in pH on dilution or on addition of small amounts of acids or alkali.
Buffers are broadly divided into two types – acidic and alkaline buffer solutions.