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

Prepare and standardize a sodium hydroxide (NaOH) solution

Determine the molecular weight of benzoic acid(C7H6O2)

OBJECTIVE

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

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

Part I: Standardization

Potassium hydrogen phthalate (KHP)KHC8H4O4

MW: 204.22 g/mol

Prepare the buretRinse with distilled waterRinse with diluted NaOH solution (student prep)

PROCEDURE NOTES

Looking for a light pink color

3 good trials Molarities within 0.01M

Check Molarities before continuing

PROCEDURE NOTES

Part II: Determining the Molar Mass of Benzoic Acid

Look for light pink color

3 good trials

PROCEDURE NOTES

Completed titrations dispose in the sink

WASTE

Hydrochloric AcidDanger Inhalation HazardCorrosive

Sodium HydroxideDanger Inhalation HazardCorrosive

RISK ASSESSMENT

Label for NaOH:

Names

Molarity

Lab Section

LABELING

CALCULATIONS

(L) volume

(mol) molesMolarity

baseacid molesmoles