AP Chemistry Lab 2
What is the Relationship Between the Concentration of a Solution and the Amount of
Transmitted Light Though the Solution? (Investigation 1; AP Chemistry Guided Inquiry
Laboratories, 2013)
Much of the experimental work of this lab was completed as the “Prelab Guiding
Questions/Simulations”. The experimental portion using the Gatorade happened quickly, and
you may have missed it! If so, make sure you get the data from someone who has it. (Adam or
Ben?)
In your lab notebook: (to be collected around Nov 1, to be part of mid-trimester assessment)
For each experiment, starting on a new page, you should have a heading including: title, date(s)
of experiment, lab partners
Following that should be notes about the lab, observations, labeled data tables, calculations,
and hand-written responses to questions asked along the way during the lab. Sketches of
particular lab set-ups or explanations about specialized devices (like spectrophotometers) are
also appropriate. Remember, the lab notebook is your record of what you did, how you did it,
and what you observed and measured. If you refer back to it in 6 months or a year, there
should be enough information to clearly jog your memory. And for someone else reviewing it,
they should understand the scope of what you did.
In your written (word-processed) report: (due 10/21)
Introduction: Discussion of concepts and context: spectroscopy, transmittance, absorbance and
purpose(s) of lab (both in terms of determining relationship between transmittance,
absorbance and concentration, and in terms of your experimental findings about Gatorade.)
Prelab: (25 points)
Summary of your procedure
Table of class data
Calculations to transform Transmittance
Graphs of each proposed relationship (labeled, titled, with linear regression and correlation
values)
Your interpretation/assessment of those graphs. (i.e. – what do they tell you about the
relationship between Transmittance and concentration?)
Essentially, you are developing the concept of Absorbance here.
Absorbance = _________. I know this because ……..
Investigation: (13 points)
Summary of procedure
Data
Calculations:
Absorbance
Concentration
Mass of blue dye #1 in 500 mL bottle
Responses to Post-lab Assessment questions 1-3 (12 points)