The missing hydrogen ion,part-1:Historical precedents vs.fundamental concepts  

作　　者：Robert Robergs Bridgette O'Malley Sam Torrens Jason Siegler 

机构地区：[1]School of Exercise and Nutrition Sciences,Queensland University of Technology,Kelvin Grove,Queensland,4059,Australia [2]ASU Health Futures Center,College of Health Solutions,Arizona State University,6161 East Mayo Blvd,Phoenix,85054,Arizona,USA

出　　处：《Sports Medicine and Health Science》2023年第4期336-343,共8页运动医学与健康科学（英文）

摘　　要：The purpose of this review and commentary was to provide an historical and evidence-based account of organic acids and the biochemical and organic chemistry evidence for why cells do not produce metabolites that are acids.The scientific study of acids has a long history dating to the 16th and 17th centuries,and the definition of an acid was proposed in 1884 as a molecule that when in an aqueous solution releases a hydrogen ion(H^(+)).There are three common ionizable functional groups for molecules classified as acids:1)the carboxyl group,2)the phos-phoryl group and 3)the amine group.The propensity by which a cation will associate or dissociate with a negatively charged atom is quantified by the equilibrium constant(K_(eq))of the dissociation constant(K_(d))of the ionization(K_(eq)=K_(d)),which for lactic acid(HLa)vs.lactate(La^(-))is expressed as:K_(eq)=K_(d)=[H^(+)][La^(-)]/[HLa]=4677.3514(ionic strength=0.01 Mol⋅L^(-1),T=25℃).The negative log10 of the dissociation pKd reveals the pH at which half of the molecules are ionized,which for HLa=3.67.Thus,knowing the pKd and the pH of the solution at question will reveal the extent of the ionization vs.acidification of molecules that are classified as acids.

关 键 词：Hydrogen ion Acid ACIDOSIS pH Equilibrium constant(K_(eq)) IONIZATION Dissociation constant(K_(d)) 

分 类 号：O62[理学—有机化学]