Optics > Color > Scattering, Synthesis and Analysis of Color
Optics > Geometrical Optics > Optical Instruments, Refractive Index
Vetted
Highlights:
This lab allows students to explore spectrophotometers and the functioning of pulse oximeters.
Abstract:
The simulated pulse-ox device uses bromothymol blue, a common pH indicator, as a blood analog. Simply breathing on a solution of bromothymol blue will introduce carbon dioxide from your breath into the solution. The CO2 reacts with the solution to form carbonic acid which increases the acidity of the solution. As the pH of the solution changes, the color of the solution also changes. In this lab, students examine the change both visually and with a spectrophotometer linking observations to the spectral characteristics of deoxygenated and oxygenated blood as measured by a pulse-oximeter.
Resource Types:
Lab, Exam problem, Instructor supplement, Project
Authors:
Justin Dunlap
Portland State University
Ellynne Kutschera
Portland State University
TOPICS
Physics Topics:
Life Sciences Topics:
Cross-cutting Biological Concepts
Human and Animal Physiology > Cardiovascular System > Cardiovascular Disorders, Healthy Cardiovascular Function
Human and Animal Physiology > Other Body Fluids
Human and Animal Physiology > Respiratory System > Respiratory Disorders
Medical Applications > Diagnostic (non-imaging) Techniques > Physical Exam
Chemistry Topics:
Electron Transfer Reactions > Electrochemistry, Redox Reactions
Math Topics:
Algebra; Exponentials and Logarithms
INSTRUCTOR GUIDE
IMPLEMENTATION
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PEDAGOGY
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SUBMISSION DETAILS
Copyright: 2021 Portland State University
License:
CC0 – Public Domain. No restrictions.
Last Edit Date:
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