If 50 ml of 0.1 HBr is mixed with 50 ml 0.2 M NaOH , find pH of resulting mixture

Step-by-step solution

N _ Mix V _ Mix = (Base) N ₁ ~V ₁ - (Acid) N ₂ ~V ₂ (i) Given, aligned M ₁ & =0.2 M , N ₁=0.2 ~N M ₂ & =0.1 M , N ₂=0.1 ~N ~V ₁ & =50 ml , V ₂ & =50 ml , V _ mix =100 ml aligned On substituting the given values is equation. (i), We get aligned N _ mix 100 & =50 0.2-50 0.1 ~N _ mix & = 5 100 =5 10⁻² [ OH ⁻ ] & =5 10⁻² aligned Now, aligned _ P OH & =- [ OH ⁻ ]=- [5 10⁻² ] & =2- 5=1.3 aligned Also, pH + pOH =14 pH =14-1.3=12.7