Question

Explain what the Kb for aniline (C6H5NH2) tells you (Kb = 4.3 x 10-10).

Answer 1

Step-by-step explanation:

C₆H₅NH₂ + H₂O = C₆H₅NH₃⁺ + OH⁻

C₆H₅NH₃⁺ is also called anilinium ion . Thus we see that aniline reacts with water to form anilinium ion and forms OH⁻ ion . Due to it, it shows basic properties . The pH value of this aqueous solution is more than 7 . But it is a weak base because the concentration of OH⁻ formed is very less . It is so due to its less value of Kb . It has been explained as follows

Kb =
`([C_6H_5NH_3^+][OH^-])/([C_6H_5NH_2][H_2O])`

Since Kb is 4.3 x 10⁻¹⁰ which is very low value so concentration of OH⁻ that is [OH⁻] formed will also be very low . Hence it will be a weak base.