My only reason for saying that the index of refraction for visible light in salt/sugar/water solutions isn't dramatically higher than plain water is that it's generally far less than a 5% change from 1.333. It's certainly less than most glasses. I was pointing out---as you did---the dramatic effects even a small change can have over many optical wavelengths.
Cheers,
Curtis O.
/************************************
Down with categorical imperative!
flutzpah@yahoo.com
************************************/
________________________________
From: "Edmiston, Mike" <edmiston@bluffton.edu>
To: Forum for Physics Educators <phys-l@carnot.physics.buffalo.edu>
Sent: Tuesday, May 12, 2009 2:21:58 AM
Subject: Re: [Phys-l] index of refraction
...
Curtis Osterhoudt said, "The index of concentrated sugar water or salt
water isn't *much* higher than for pure water..."
Response: I don't know where this is coming from. The demonstration of
the difference, when done properly, is dramatic. This is the way
vintners measure the sugar content of their grapes. You can buy
portable pocket refractometers for measuring sugar in water (also for
measuring salt in water). Unfortunately they are expensive. The J Chem
Ed publication explains how to make your own sugar-water
refractometer... but it won't fit in your pocket.
REFERENCES:
"A Liquid Prism for Refractive Index Studies", Edmiston, Michael D., J.
Chem. Educ., 78, p. 1479 (2001).
"Measuring Refractive Indices, Michael D. Edmiston, The Physics Teacher,
Volume 24, Issue 3, pp. 160-163 (1986).
Link for directions for hollow glass prism fabrication...
www.bluffton.edu/~edmistonm/hollow.prism.directions.pdf
Link of preprint of the J Chem Ed paper. This may be a working version
and may differ slightly from the published version (I did not check it
word-for-word).:
www.bluffton.edu/~edmistonm/liquid.prism.pdf
Michael D. Edmiston, Ph.D.
Professor of Chemistry and Physics
Bluffton University
Bluffton, OH 45817
(419)-358-3270
edmiston@bluffton.edu