Solution of 0.1 ~N NH ₄ OH and 0.1 ~N NH ₄ Cl has pH~ 9.25 , then find out pK _b of NH ₄ OH .

Step-by-step solution

Concentration of salt NH ₄ Cl =0.1 ~N Concentration of the base NH ₄ OH =0.1 ~N pH of solution is 9.25 pOH =14- pH =14-9.25=4.75 We know that, pOH = pK _ b + [ salt ] [base ] (But here concentration of salt = concentrtion of base and [ ₁₀(1)- .0] . pOH =p ~K _b=4.75 A Caution aligned NH ₄ OH & NH ₄⁺ Cl ⁻ NH ₄ Cl & NH ₄⁺+ Cl ⁻ aligned Due to the common ion effect, the reaction of dissociation of NH ₄ OH shifts to the left.