Post-Lab Questions
1. A beverage company is having trouble with the production of the dye in their drinks. The color of their drink mix is supposed to be a pale green color, but they often get different results. For each unwanted result, choose the most plausible explanation to help the company improve the formula.
(1pts)
The color of the drink is too pale after adding the dye to the drink because
Choose...too much dye was added to the drink.the water in the drink is evaporating.not enough dye was added to the drink.the wrong dye was added to the drink.
(1pts)
The color of the dye is appearing as red, instead of green because
Choose...too much dye was added to the drink.the water in the drink is evaporating.not enough dye was added to the drink.the wrong dye was added to the drink.
(1pts)
The drink started out the correct color but it is getting darker over time, even though nothing has been added to the drink, because
Choose...too much dye was added to the drink.the water in the drink is evaporating.not enough dye was added to the drink.the wrong dye was added to the drink.
(1pts)
2. Beer's Law states that A=εbc, where A is the absorbance, ε is the molar absorptivity of the solute, b is the path length, and c is the concentration. Identify the experimental evidence from the activity that you have for the dependence of absorbance on each variable.
The evidence for the dependence of absorbance on the variable ε is
increasing the cuvette width increases the absorbance.
changing the compound changes the absorbance behavior.
adding more water decreases the absorbance.
Choose...ABC
(1pts)
The evidence for the dependence of absorbance on the variable b is
increasing the cuvette width increases the absorbance.
changing the compound changes the absorbance behavior.
adding more water decreases the absorbance.
Choose...ABC
(1pts)
The evidence for the dependence of absorbance on the variable c is
increasing the cuvette width increases the absorbance.
changing the compound changes the absorbance behavior.
adding more water decreases the absorbance.
Choose...ABC
(1pts)
3. Describe how you could use the Beer's Law simulation to experimentally determine the best wavelength at which to perform an experiment.
Measure the absorbance for solutions of multiple different solutes and find the minimum absorbance.
Measure the absorbance for solutions with different concentrations and find the slope of the trendline.
Measure the absorbance for the same solution at different wavelengths and find the maximum absorbance.
Measure the absorbance for the same solution in different cuvette sizes and find the y-intercept.