 What we have here is a spectrophotometer, and we're going to use it to quantitatively tell us something about the energy via the wavelength that is absorbed by a solution. So if you remember our slime, we had looked green in one place and then looked red in another. So the way the spectrovis works is there's a light source here, we have a cuvette and we put our sample here, and every time you use this you have to calibrate. So we're going to calibrate first with water because our solutions were made with water. We're going to go to our screen now and so you can see the spectrovis is connected to the computer and we have software that is going to collect the data for us. But first we have to tell the software what is a two-point calibration which means that there is what the amount of light is actually passing through. So if you look carefully right here you can see it's doing a scan of all of the visible wavelengths and it's telling the software that 100% of the light is being transmitted with the water. Now that we are calibrated we're going to take this cuvette out and we're going to put our sodium borate sample into that spectrophotometer. Now that we have our sample and our spectrophotometer we can collect the data. So what the spectrophotometer is doing is it's running a scan for each wavelength. So you can see from this is actually 450 to about 750 nanometers. So I'm going to stop this and what you can see is all of this is well none of it is being absorbed. So that means all of the red is being transmitted. Yellow, green and blues are being absorbed. So that's the reason when we held our slime up to the white light it looked red because that was what was being transmitted. So we can calculate the energy of each of those by knowing the wavelength and the speed of light.