Question

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

Answer 1

Answer:

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 = $\frac{[C_6H_5NH_3^+][OH^-]}{[C_6H_5NH_2][H_2O]}$

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.