Pawan
NaOH reacts with CH3COOH in 1:1 molar ratio. You are mixing equimolar amounts of the two reactants . You will produce a solution of CH3COONa Mol CH3COOH in 50.0mL of 0.1M solution = 50/1000*0.1 = 0.005 mol CH3COOH This will produce 0.005 mol CH3COONa dissolved in 100mL = 0.1L solution Molarity of CH3COONa solution = 0.005/0.1 = 0.05M CH3COONa solution. Ka CH3COOH = 1.8*10^-5 Kb = 10^-14 / ( 1.8*10^-5) Kb = 5.56*10^-10 Use Kb equation to calculate [OH-] Kb = [OH-]² / [CH3COONa] 5.56*10^-10 = [OH-]² / 0.05 [OH-]² = (5.56*10^-10)* 0.05 [OH-]² = 2.78*10^-11 [OH-] = 5.27*10^-6 pOH = - log [OH-] pOH = -log ( 5.27*10^-6) pOH = 5.28 pH = 14 - pOH pH = 14 - 5.28 pH = 8.72...this will be wright ans