Primary Productivity Lab Report Resources

Titration is a technique common in chemistry laboratories, used to find the concentration of a substance by slowly adding a known amount of another substance.

For your methods section, I would like to see:

1. a brief summary of what you did, so...

• what was the general setup of the lab?
• how did you go about determining the effect of the intensity of light on primary productivity?
• what was this titration you carried out? Why did you do it? What were you looking for?

2. your independent and dependent variables, the control and experimental groups, as well as any constants

3. a diagram of the setup of your experiment

Want some background information that will take you (sort of) through the titration and could be helpful to write a very strong methods section? Here you go!

The class data is posted here but I have not received all of it. This makes sense for 11BD, but Table 3/4 in 12BD is slacking hard and I suggest that this is rectified sooner than later.

IMPORTANT USEFUL PIECE OF INFORMATION - I measured the Initial DO for 3 tables and each time I found it to be between 1.22 mg/L and 1.24 mg/L. Some students were concerned about their Initial DO values being lower than their Dark DO values, so this could help.

Sample Data

	Initial DO (mg/L)	100% DO (mg/L)	65% DO (mg/L)	25% DO (mg/L)	10% DO (mg/L)	2% DO (mg/L)	Dark DO (mg/L)
Class Data	6.3	7.95	7.85	7.3	6.55	5.6	4.1

Want some background information that could be useful in the introduction? Here you go!

A model data analysis section is posted here. It delineates what could (should?) be present in a thorough analysis of data and how it corresponds to the rubric. NOTE: This analysis is good, but not perfect. It does not explicitly/thoroughly address the productivity of the algae, instead it only discusses how photosynthesis occurred. Also, the graph shows the amount of oxygen produced by the algae, but the lab report overview asks for the gross and net productivity under each light. This can all fit on one graph. To repeat, you only need one graph that shows the gross and net productivity for the algae under each lamp.

Want to see the rubric that will be used to assess your lab report? Here you go!