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Measuring the concentration of dye

  1. Oct 9, 2008 #1
    I was wondering if someone could help me understand how to measure different concentrations of dye in water.
    My experiment is to test out different concentrations of dye, that will be able to change the color of a flower.
    I didnt want to use the simple way of putting 1 drop, 2 drop, etc...in water, and measuring it that way.
    I think it can be measured in moles, but i only understand it when using sugar/salt, in water. I can't understand liquid in liquid, like dye in water.
    can anyone help?
    i'll appreciate it very much. :)
  2. jcsd
  3. Oct 9, 2008 #2


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    Dyes are very very colored compounds, which means that only small amounts will be very apparent in solution. If you were going to measure moles, how would you do it? Would you evaporate the water off and weigh the solid (not easy) and do the math knowing the formula weight? Would you measure the absorbance of the solution and correlate it to known concentrations of the dye? (very easy) Most dyes are solids that are dissolved in solution. Concentrated solutions are often diluted in their final application since only a small error in measuring mass will cause a massive error in the apparent color.
  4. Oct 9, 2008 #3


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    UV/Visible Spectroscopy. Interest in absorbance.
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