Question

欲配置ph=4.7的缓冲溶液500ml,问应用50ml0.5mol/lNaOH和多少ml0.5mol/LHAc溶液混合再

Answer 1

PH=PKa-lgc(HAc)/c(Ac-)

4.7=4.75-lgc(HAc)/c(Ac-)

lgc(HAc)/c(Ac-)=0.05

c(HAc)/c(Ac-)=112/100

n(Ac-)=n(NaOH)=0.5×0.05=0.025mol

n(HAc)=0.025×(112/100+1)=0.053mol

需要0.5mol/LHAc溶液体积1000×0.053/0.5=106ml