一元弱酸HA和HB混合溶液的pH计算  

The pH Calculation of the Mixed Weak Acids of HA and HB Solutions

作　　者：何大卫 王海水[1] Dawei He;Haishui Wang(School of Chemistry and Chemical Engineering,South China University of Technology,Guangzhou 510640,China)

机构地区：[1]华南理工大学化学与化工学院,广州510640

出　　处：《大学化学》2021年第6期217-221,共5页University Chemistry

基　　金：国家自然科学基金(21773072)。

摘　　要：对于一元弱酸HA或HB的纯溶液,如果CHAKHA>10KW和CHBKHB>10KW,则可用一元弱酸溶液中H^(+)浓度的近似式分别得到纯HA溶液的[H^(+)]_(HA)和纯HB溶液的[H^(+)]_(HB)。本文研究了HA和HB混合酸溶液近似氢离子浓度[H^(+)]_p与[H^(+)]_(HA)和[H^(+)]_(HB)的关系。研究表明,如果允许[H^(+)]_p与混合酸溶液准确氢离子浓度[H^(+)]_T有±5%误差(±0.02 pH),则本文提出的新公式_p^([H+])满足近似计算要求。使用[H^(+)]p式条件:CHA≥2KHA和CHB≥2KHB。[H^(+)]p近似式简单,适用浓度范围宽,为一元酸混合溶液pH计算带来便利。A novel approximate formula[H^(+)]p is proposed to obtain the pH of the mixed HA and HB solutions,where[H^(+)]HA and[H^(+)]HB are the estimated values of[H^(+)]for HA solution and HB solution,respectively.If cHA³2KHA and cHB³2KHB,[H^(+)]p formula will work very well.The novel approximation formula is simple,easy to remember,and can be widely used to calculate the pH of the mixed monoprotic weak acid HA and HB solutions.

关 键 词：一元弱酸 混合溶液 PH 近似式 

分 类 号：G64[文化科学—高等教育学] O6[文化科学—教育学]