COLORIMETRY
a Guided - Inquiry Simulated Experiment
by
Gary L. Bertrand
Missouri University of Science and Technology

Your Unknown Code #:

this may be replaced by any number from 101 to 999

Go to Experiment

In this experiment, you are given the following solutions:

(1)   standard red dye (14 ppm)

(2)   standard blue dye (12 ppm)

(3)   distilled water

(4)   an unknown mixture of the red or blue dye with distilled water

(5)   an unknown mixture of the red and blue dyes

and the following equipment:

            a plastic Beral pipet which delivers drops of uniform size

            two strips of 9 “microbeakers” which hold 8 drops of liquid.

 


Your Assignment:

(1)   To determine the fraction of red or blue dye diluted with distilled water in solution #4.

(2)   To determine the fraction of red dye mixed with blue dye in solution #5.

 

When you are satisfied that you have determined these values, click on the links to check your answers.

For the red or blue unknown, you will be first asked to give the volume of red or blue dye divided by the total volume of distilled water and dye solution which gives a color closely matching Unknown #4.  If you get this right, you will be asked for the ppm of dye in Unknown #4.

For the purple unknown, you will be first asked to give the volume of red dye divided by the total volume of red and blue dyes which gives a color closely matching Unknown #5.  If you get this right, you will be asked for the ppm of red dye in Unknown #5, then for the ppm of blue dye in Unknown #5.