For the teacher-led class demonstration:

• Disappearing Glass Demo Instructions
• two 500-ml clear glass beakers
• glycerin (or vegetable oil, such as Wesson; glycerin is preferred; see note below)
• water
• 2 Pyrex stirring rods, such as the 12-inch clear glass stir rod available for $1.75 each at The Science Company website at https://www.sciencecompany.com/Clear-Glass-Stir-Rod-12-inch-P17256.aspx

Each group needs:

• poster board and writing utensils (or a small white board and a dry erase marker)
• Refractive Index Lab Worksheet
• (optional, for activity extension assignment) Refractive Index Application Research Questions

For Part 1, each group needs:

• laser pointer
• print out of a polar graph; such as the example graphs found at the University of South Florida's Florida Center for Instructional Technology ClipArtETC website at http://etc.usf.edu/clipart/43000/43018/polar_24-4l_43018.htm
• (optional but recommended) plastic sheet protector to protect the paper polar graph from spills
• clear tape
• semicircular hollow acrylic block, 12 cm diameter x 2.5 cm high, available (part# RCSC01) at Nova-Tech International at http://www.novatech-usa.com/RCSC01
• ~50 ml water
• ~50 ml glycerin (or vegetable oil, such as Wesson), such as ACS grade, 4-liter bottle of glycerin (catalog # S25342D) from Fischer at https://www.fishersci.com/shop/products/glycerin-4l-acs-grade/s25342d; glycerin is preferred because it is the same color as water so students will not realize at first that the two liquids are different, and it is soluble in water, making clean-up easier

For Part 2, each group needs:

• laser pointer
• LED lights/semiconductors (matching the color of the laser used), such as the LED semiconductors from Sargent Welch for a pack of five at https://sargentwelch.com/store/product/8887114/led-semiconductors
• 4 containers (cuvettes are preferred, but small test tubes also work)
• ~6 ml water
• ~6 ml glycerin (or vegetable oil, such as Wesson)
• 2 Pyrex glass tubes (~6 cm in length each) that fit in the sample container, as shown in Figure 2; such as "Rod, glass, Pyrex, 3 mm OD (outer diameter)," catalog # 239430, page 193 in University of Houston's Research Stores 2013 Catalog, for ~$1 per piece (~1.5 meter) at http://researchstores.nsm.uh.edu/catalog, Pyrex brand is necessary to get the desired results
• sample container rack or holder to securely hold vials of four samples, such as the one shown in Figure 2 made with cardboard, clear tape and two packing foam pieces
• multimeter
• electronic breadboard and electrical wire (optional but recommended to ensure the stability of the detector), such as the five mini solderless prototype breadboards with 170 tiepoints available for $6.67 at http://www.ebay.com/itm/5x-Transparent-Mini-Solderless-Prototype-Breadboard-170-Tie-points-for-Arduino-/231242048856?pt=LH_DefaultDomain_0&hash=item35d719a558 or www.amazon.com.

To share with the entire class:

• (optional but recommended if available) lux meter, to verify the reliability of the results from the homemade LED-multimeter light intensity detector; such as Mastech's light meter LX1010B, 50,000 Lux Luxmeter with LCD display for $15 (MSRP $50) at https://www.amazon.com/Light-Meter-LX1010B-Luxmeter-display/dp/B000JWUT6O