Basic instructions for using Vernier Colorimeter.

Equipment:

• Vernier colorimeter
• (cuvettes with lids-should be in with colorimeter)
• Go-link

Setting Up

(from the Vernier instruction booklet accompanying the instrument):

1. Turn on your computer and open Logger Pro 3
2. Plug the Colorimeter into Go-Link! and plug Go-Link! into a USB port on your computer. The software should automatically detect the probe and switch to a screen showing "Transmittance" in the lower left corner. Columns will show: Time, Trans, Abs.
   • The Colorimeter will take about 5 minutes to warm up. Keep this in mind...
3. Rinse the cuvettes inside and outside to make sure they are clean. They are made of polystyrene and can scratch - please do not rub them hard with paper towels, use lens paper.
4. Place your sample solutions into your cuvettes. In most cases you need a "standard" for reference so make one and identify it in your data.
5. Select the wavelength: 430 nm = violet, 470 nm = blue, 565 nm = green, 635 nm = red
   • Select the wavelength closest to the recommended one.
   • If a wavelength is not recommended, consider that the color of the solution indicates the light being transmitted by the solution; other colors are being absorbed (try it!).
   • Therefore you need to select a different color than the one in the cuvette. Try each wavelength and choose the one with the highest absorbance.
6. Place the standard in the Colorimeter. Give it a few seconds to "settle" then press "CAL" on the colorimeter (not the computer). This will zero the instrument to your standard.
7. Take several readings using the computer. You should have 15 readings to establish a mean; minimum 7 readings.
   • Click on "data collection" in heading of Logger Pro graph
   • Change collection time to 30 seconds
   • Change collection interval to one collection every 2 seconds (15 collections in total)
8. On graph, axis labels can be changed by clicking on axis labels. Popup menu give you options for axis label names. This can be done before or after data collection.
9. Click "Start" in upper right hand corner to start data collection. It will stop automatically after the assinged collection period.
10. Store each data collection as a unique file name (to keep track of them for later.)
    • Save them to easy to find location (like your desktop!)