Testing the Efficiency of the Carbon Dioxide-to-Oxygen Conversion (Part 2, Experiment 1)

Part 2: Testing the Release of Carbon Dioxide

After the carbon dioxide meters have been calibrated, two tests must be done since the carbon dioxide can be released in two ways into the atmosphere: escape directly as carbon dioxide through the hole on the plant's side of the device; convert into oxygen through photosynthesis and get released into the atmosphere through the hole on the plant's side of the device.
The tests will help gather data in either situation of how much carbon dioxide is returning to the atmosphere and how much is getting converted into oxygen.

EXPERIMENT #1

The first way in which carbon dioxide can be released back into the atmosphere is by directly leaving through the hole in the plant compartment. The set-up to measure the air exchange is the same as the set-up to calibrate the carbon dioxide meters. In order to measure how much of the carbon dioxide is getting released back into the atmosphere, an empty container will be exposed to pure carbon dioxide from the carbon dioxide tank. The empty container will have a carbon dioxide meter inside it to test for the changes in the concentration of carbon dioxide, which would indicate the release of carbon dioxide. Since it is an empty container with carbon dioxide, the concentration should not fluctuate much over a duration of time (ten minutes) and would show how concentrated the carbon dioxide will be when not converted into carbon dioxide. 

EXPERIMENTAL DATA

This week, experimentation has been done to measure air exchange rate for determining the efficiency of English ivy to eliminate CO₂ from the atmosphere. The first test was done by monitoring CO₂ using two sensors in a closed container with only an opening for CO₂. Through that opening, CO₂ was inserted and quickly closed. The entire container was also sealed off so that there was no air exchange with the outside environment. The concentration of CO₂ over time was monitored and then used in an equation to calculate air exchange. The equation we used was as follows:
 

Using this formula, we were able to plot the data versus time to get a line equation of the rate of air exchange without plants. Two experiments were done for each sensor. Using the equation of the lines of each, the slope was determined and averaged for each sensor to get an average rate exchange for each sensor. The average rate for sensors 1 and 2 were .09020 ppm CO₂/ hour and .06435 ppm CO₂/hour, respectively. The data is shown below: