IB›IB Chemistry SL›Mind mapsR3.1 Proton transfer reactionsIB Chemistry SL: Mind mapStudy pack PDFAlso for this subtopic:Revision notesFlashcardsSubtopic testCover factsBrønsted–LowryAcid = proton donorBase = proton acceptorConjugate pair differs by one H⁺Conjugate base of HX2SOX4\ce{H2SO4}HX2SOX4 is HSOX4X−\ce{HSO4-}HSOX4X−Amphiprotic: HX2O\ce{H2O}HX2O, HCOX3X−\ce{HCO3-}HCOX3X−, HSOX4X−\ce{HSO4-}HSOX4X−pH and KwpH=−log10[HX+]\text{pH} = -\log_{10}[\ce{H+}]pH=−log10[HX+]1 pH unit is a tenfold change in [HX+][\ce{H+}][HX+]Kw=[HX+][OHX−]=1.00×10−14K_w = [\ce{H+}][\ce{OH-}] = 1.00 \times 10^{-14}Kw=[HX+][OHX−]=1.00×10−14 at 298 KNeutral means [HX+]=[OHX−][\ce{H+}] = [\ce{OH-}][HX+]=[OHX−], not pH 7[OHX−]=2.0×10−3[\ce{OH-}] = 2.0 \times 10^{-3}[OHX−]=2.0×10−3 gives pH 11.30Strong vs weakStrong: fully ionisedWeak: partly ionised, equilibriumStrength is not concentrationWeak acid: higher pH, lower conductivityEquilibrium lies towards the weaker conjugateAcids & basesproton transferH⁺pHKwNeutralisationAcid + base → salt + waterCaCOX3+2 HCl→CaClX2+HX2O+COX2\ce{CaCO3 + 2HCl -> CaCl2 + H2O + CO2}CaCOX3+2HClCaClX2+HX2O+COX2HX+(aq)+OHX−(aq)→HX2O(l)\ce{H+(aq) + OH-(aq) -> H2O(l)}HX+(aq)+OHX−(aq)HX2O(l)Carbonates give effervescence (CO₂)pH curveStrong acid with strong base starts at pH 1Steep rise from about 3 to 11Equivalence at pH 7 (298 K)Levels off near pH 13Exam tipsRemove only one proton for the conjugate baseKw changes with temperatureMark start pH, equivalence volume and plateau