Aniline, abbreviated fNH2, where f is C6H5, is an important organic base used in the manufacture of dyes. It has a Kb of 4.3 * 10^(-10). In a certain manufacturing process, it is necessary to keep the concentration of fNH3+ (aniline’s conjugate acid, the anilinium ion) below 1.0 * 10^(-9) M in a solution that is 0.10 M in aniline. Find the concentration of NaOH required for this process.

Verified step by step guidance

1. Identify the equilibrium reaction: Aniline (C6H5NH2) reacts with water to form its conjugate acid (C6H5NH3+) and hydroxide ions (OH-).
2. Write the expression for the base dissociation constant (Kb): Kb = [C6H5NH3+][OH-] / [C6H5NH2].
3. Substitute the known values into the Kb expression: Kb = 4.3 \times 10^{-10}, [C6H5NH3+] = 1.0 \times 10^{-9} M, and [C6H5NH2] = 0.10 M.
4. Solve for [OH-] using the Kb expression: [OH-] = (Kb \times [C6H5NH2]) / [C6H5NH3+].
5. Determine the concentration of NaOH required, which is equal to the concentration of OH- calculated in the previous step.