8. Did the pH increase or decrease with the plant under the green filter?
Notice the light produced with the green filter is only green. Remember that chlorophyll is green indicating that the green wavelength are reflected, not absorbed (notice the dips in the graph above in the wavelengths). Since green light is not absorbed, very little photosynthesis will occur. Since photosynthesis does not occur, no CO2 is taken up and very little change in pH will occur.