Quantities and Reactions : General Redox

Discover how pH affects the oxidizing or reducing strength of a chemical.

Lab Summary:

In this exploration you will use PASPORT pH and ORP electrodes to investigate increasing and decreasing the pH of a solution of bleach and how this affects the effectiveness of the bleach as a disinfectant.

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(student version)

Method:

Use PASPORT pH and ORP electrodes to investigate increasing and decreasing the pH of a solution of bleach and how this affects the effectiveness of the bleach as a disinfectant.

Here's What You Need:

Probeware

• PASPORT Chemistry Sensor (PS-2170)
• Xplorer GLX Graphing Datalogger (PS-2002)
  (or alternate PASPORT interface -- see other options)

Other Materials

• Small Tripod Base & Rod (SE-9451)
• Buret Clamp (SE-9446)
• Magnetic Stirrer (SE-7700)
• ORP Electrode (CI-6716)
• Beaker, 150-mL
• Plastic dropper
• Wash bottle and waste container
• Sodium hypochlorite (household bleach)
• 0.5 M hydrochloric acid (HCl)
• 0.5 M ammonium hydroxide (NH₄OH)

Lab Manual:

This activity is included in Chemistry with the Xplorer GLX (PS-2819A), complete with Teacher Information pages, student instructions and handouts, and sample data for a total of 19 probeware-based labs. For your convenience, we offer bundles which provide the probeware necessary for the activities in the manual. For more information on these resources and bundles, click here.