1. ACID-BASE TITRATION Due Today: 1. Acid-Base Titration Pre- Lab 2. Gravimetric Analysis of Phosphorus Formal Lab Report Homework: 1. Acid-Base Short Report 2. Neutralizing Power of Antacids Pre-Lab

2.  Prepare and standardize a sodium hydroxide (NaOH) solution  Determine the molecular weight of benzoic acid(C 7 H 6 O 2 ) OBJECTIVE

3.  Titration – process of reacting a solution of unknown concentration with a solution of a known concentration until the reaction is JUST complete  All reactants are limiting KEY TERMS

4.  Equivalence Point – equal quantities of opposite solutions exist  Moles of acid = Moles of base  For Today’s Experiment:  Moles of KHP = moles of NaOH  Moles of NaOH = moles of Benzoic Acid KEY TERMS

5.  Part I: Standardization  Potassium hydrogen phthalate (KHP)  KHC 8 H 4 O 4  MW: 204.22 g/mol  Prepare the buret  Rinse with distilled water  Rinse with diluted NaOH solution (student prep) PROCEDURE NOTES

6.  Looking for a light pink color  3 good trials  Molarities within 0.01M  Check Molarities before continuing PROCEDURE NOTES

7.  Part II: Determining the Molar Mass of Benzoic Acid  Look for light pink color  3 good trials PROCEDURE NOTES

8.  Completed titrations dispose in the sink WASTE

9.  Hydrochloric Acid  Danger  Inhalation Hazard  Corrosive  Sodium Hydroxide  Danger  Inhalation Hazard  Corrosive RISK ASSESSMENT

11.  Label for NaOH:  Names  Molarity  Lab Section LABELING

12. CALCULATIONS