Answer:
D) 7.1 x 10-4
Explanation:
Kb = 1.4 x 10^-9
Ka = ?
Relationship between Ka and Kb is given by:
Ka x Kb = Kw
where Kw = ion product constant which relates the concentrations of acids/bases and their conjugates in a solution. The value of this constant is 1.0 × 10^-14
Ka = Kw / Kb
Ka = (1.0 × 10^-14) / (1.4 x 10^-9)
Ka = 0.7142 x 10^-5
Ka = 7.142 x 10^-4
Correct option is D.