eTitratorThe Online Titration Calculator

Kevin NgoDepartment of Chemistry

Central Washington UniversitySOURCE, May 2014

Concepts Chemical Equilibrium

General Chemistry Acid Base Titration

Confusing and Difficult Calculations

Introduction

Currently Implemented Future• Interface• Simple Input• Advanced Input• Graphical Visualization of

Titration• General Chemistry pH

Calculation• Strong Titrant• Strong and Weak Analytes • Monoprotic and Polyprotic

Acids

• Interface• Cell phones and

Tablets• Step by Step Tutorial• Problem Generator

Features

Software Up-to-date Web Browsers

Operating System Windows Mac Linux/UNIX iOS/Android

Platform Requirements

Application Programming Interface

Titration System

Acid-Base

HTML

Titration Wrapper

Complexometric

Redox

Real Life EquivalencepH Meter

Indicator

Potentiometer

Abstraction

Representative

User Interaction

General Approach Before titrant is added Buffer region(s) At equivalence point(s) Beyond equivalence point (titrant in excess)

Approximations Hiccups where it should be smooth

Calculation Method

Calculation Method (cont.)

Is Analyte Strong?

Weak Analyte Calculations

Strong Analyte Calculations

Yes

No

Buffer

Equivalence Point

Titrant in Excess

Situation Equation

Some Equations Used

𝑝 𝐻=− log ¿¿Strong Acid in Excess

Buffer Region

Henderson-Hasselbalch Equation 𝑝𝐻=𝑝𝐾𝑎+ log( [𝐵𝑎𝑠𝑒 ]

[ 𝐴𝑐𝑖𝑑 ] )

Pure Weak Acid𝑝𝐻=

𝑝𝐾 𝑎− log ( [ 𝐴𝑐𝑖𝑑 ] )2

1M HCl vs 1M NaOH1M NaOH vs 1M HAc4M NaOH vs 4M H3PO4

Demonstration

NaOH vs H3PO4

Expanded Titration FunctionsAccurate pH Titrations (done w/ Fortran)Redox, Gas Phase, and Complexometric Titrations

First step towards an answer engine for chemistryTitrationThermodynamic PropertiesKinetic Mechanisms such as Michaelis-Menton mechanismSpectrum Analysis: UV-Vis, IR, Raman, NMR, and Mass Spectrum

Future Work

Physical Chemistry III class and Dr. Yingbin Ge’s Research Group

Department of Chemistry

Acknowledgements

Harris, D. C. (2010). Quantitative chemical analysis (8th ed.).

New York: W.H. Freeman and Co..

McQuarrie, D. A., & Rock, P. A. (2011). General chemistry (4th

ed.). Mill Valley, CA: University Science Books.

References

Questions and Comments?