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Pharmaceutical Analytical Chemistry. 213 PHC Dr. Mona AlShehri 5th Lecture. Acid-Base Titrations (1). (1) Gary D. Christian, Analytical Chemistry, 6 th edition. By the end of the lecture you should be able to:. Explain the different stages of strong and weak acid-base titration curves.
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Pharmaceutical Analytical Chemistry 213 PHC Dr. Mona AlShehri 5th Lecture
Acid-Base Titrations (1) (1) Gary D. Christian, Analytical Chemistry, 6th edition.
By the end of the lecture you should be able to: • Explain the different stages of strong and weak acid-base titration curves. • Calculate the pH at these stages.
An acid-base titration involves a neutralizationreaction ( an acid is reacted with equivalent amount of base) • A titration curve is constructed by plotting the pH of the solution as a function of the volume of the titrant added • The titrantis always a strong acid or base • The analyte may be either a strong acid or base or a weak acid or base
Strong acid versus strong base Both titrant(NaOH) and analyte(HCl) are completely ionized e.g. titration of HCl with NaOH HCl + NaOH NaCl + H2O
Strong base versus strong acid Both titrant(HCl)and analyte(NaOH)are completely ionized e.g. titration of NaOH with HCl NaOH + HCl NaCl + H2O
Weak acid versus strong base The analyte (CH3COOH) is partially ionized e.g. titration of CH3COOH with NaOH CH3COOH + NaOH CH3COONa + H2O
Weak base versus strong acid The analyte (NH3) is partially ionized e.g. titration of NH3 with HCl NH3 + HCl NH4Cl
Summary • Strong and weak acid-base titration curves. • pH calculations.