Cliffs AP Chemistry, 3rd Edition

A Sample Lab Report

I. Determining The Percent Sodium Hypochlorite in Commercial Bleaching Solutions

II. Date:1/22/98

III. Purpose:Determine the percent sodium hypochlorite in various commercial bleaching so-
lutions by titration. Compare the cost effectiveness of different brands of commercial bleaching
solutions.

IV. Theory:Commercial bleaching solutions are preared by reacting chlorine (Cl 2 ) with a base.
If the base is sodium hydroxide (NaOH), the product is sodium hypochlorite (NaOCl).
Commercially available bleaching solutions usually contain NaOCl.

V. Procedure:Refer to Chemical Education Resources, Modular Laboratory Program in
Chemistry, 1992**.

VI. Results:

brand name of commercial bleaching solution Clorox Bleach and Hughes Bleach

cost of commercial bleaching solution per gallon Clorox $1.49 per gallon

Hughes $1.50 per gallon

molarity of Na 2 S 2 O 3 solution, M Clorox 0.1 Hughes 0.1

volume of diluted bleaching solution titrated, mL Clorox 25 Hughes 25

final buret reading, mL Clorox 25.9 Hughes 41.85

initial buret reading, mL Clorox 0 Hughes 0

volume of Na 2 S 2 O 3 solution used, mL Clorox 25.9 Hughes 41.85

volume of commercial bleaching solution titrated, mL Clorox 10 Hughes 10

mass of commercial bleaching solution titrated, g Clorox 10.041 Hughes 10.945

Part III: AP Chemistry Laboratory Experiments