25摄氏度时向20mL0.1mol/L HCl中滴加0.1mol/L NaOH溶液.求所得溶液pH(1)加NaOH19.5mL(2)加NaOH19.98mL(3)加NaOH20.02mL(4)加NaOah20.5mL

问题描述:

25摄氏度时向20mL0.1mol/L HCl中滴加0.1mol/L NaOH溶液.求所得溶液pH
(1)加NaOH19.5mL
(2)加NaOH19.98mL
(3)加NaOH20.02mL
(4)加NaOah20.5mL

化学计量点前,HCl过量,c(H+)=0.1*(盐酸的体积-加入氢氧化钠的体积)/(盐酸的体积+加入氢氧化钠的体积)(1)加NaOH19.5mLpH=2.9c(H+)=0.1*(20-19.5)/(20+19.5)=0.0013mol(2)加NaOH19.98mLc(H+)=0.1*(20-19.98)/(20+19.98...