Equivalent conductance of 0.1 M HA (weak acid) solution is 100 cm2 equ...
Given:
- Equivalent conductance of HA solution = 100 cm2 equivalent-1
- Molar conductivity at infinite dilution = 200 S cm2 mol-1
To find: pH of HA solution
Step 1: Calculate the equivalent conductance at infinite dilution (Λ∞)
The equivalent conductance at infinite dilution (Λ∞) can be calculated using the formula:
Λ∞ = Λm - K√C
where Λm is the molar conductivity of the solution, K is a constant, and C is the concentration of the solution.
Given that Λ∞ = 200 S cm2 mol-1 and C = 0.1 M, we can substitute these values into the formula to find K:
200 = 100 - K√0.1
Solving for K:
K√0.1 = 100
K = 100/√0.1
K ≈ 316.23
Substituting the value of K back into the previous formula:
Λ∞ = 100 - 316.23√C
Λ∞ = 100 - 316.23√0.1
Λ∞ ≈ 100 - 316.23(0.31623)
Λ∞ ≈ 100 - 100
Λ∞ ≈ 0 S cm2 mol-1
Step 2: Calculate the degree of ionization (α)
The degree of ionization (α) can be calculated using the formula:
α = Λ/Λ∞
Given that Λ = 100 cm2 equivalent-1, we can substitute this value into the formula to find α:
α = 100/0