Building a Spectrophotometer

-
For my Instrumental Analysis class (CHEM 4100) we were asked to build a working spectrophotometer.  This was to help us better understand how an instrument is put together and how it functions.

A spectrophotometer is an instrument that measures the amount of light of a specified wavelength which passes through a medium.  The general requirements we were required to have were a light source, a diffraction grating, a sample holder, and a light detector.
1116_absorbance spectrophotometer

We were required to have a procedure that had all the materials listed as to how to make it, and how to assemble it.  The assignment was due Tuesday, and we had to bring our fully assembled spectrophotometer into class to see if it actually worked.  Our instruments were tested based on how it acquired measurements from Red-40 solutions, and these solutions were plotted to give a Beer's Law Graph (A=ElC), where A is absorbance, E is the molar absorptivity constant, l is the path length (usually 1), and C is the concentration.

This is my spectrophotometer:


My light source, is obviously the huge flashlight, the diffraction grating is the CD, the light is hitting, we were actually provided sample holders, or could have made one out of a clear hairspray cap or something, the light detector was a combination of a photoresistor and a multimeter to read the resistance.  
I turned it in and presented on it Thursday, and I'm proud of how well it worked.

Comments

Post a Comment

Popular posts from this blog

August

-
Image
 When I go back and think, I may not have taken a picture of the dinners I made.  Nope no picture of the Cajun fried rice or the Cajun chicken pasta .  I even tried to remind myself to take a picture of it as my lunch, and even that was a no.   Guess I'll start with the fried rice since I made that first.  I think it seemed simple enough, and I was almost positive I had all of the ingredients or if not a substitute, as I switched the brown rice out for white.  For the life of me I kept forgetting to look and make sure we had shrimp, but also take it out to defrost.  Our freezer is not that big, but the shrimp was all the way in the back behind baked goods, chicken, berries and a few other things I forgot were in there.   Shrimp came out and defrosted day of, although I don't think they were deveined so they took a little more prep work once the cooking started.  Side note, my coworker had mentioned making shrimp tacos and I thought...
Read more

July

-
Image
  Yikes!  Did the last month or so get away from me or what.  I had honestly started this, well prepped this a month ago, and then apparently life happened.  So before I'm two months behind, what did I make in July.   I made lots of things with cream cheese, and if you keep up more will come, a because these mini cheese cakes were a bit of a cheat while I yet again wait on buying something that I may not have room for in my kitchen right now.  Yes a springform pan takes up less room then a stand mixer, but how often will I use it?  Actually if I had one I might use it as regularly as I am my muffin tin and donut pan.  Well, maybe not but at the rate I'm going at least once every couple months.   Now I went with mini cheesecakes to lets say ease myself into it.  I've had most if not all the ingredients for a month, and was just waiting for the right time, and I may have pushed back because cheesecake isn't really a summer treat...
Read more

List of Making

-
 I've got a few things scattered here and there, and pins saved for a rainy day but if I write them here maybe make myself more accountable they might be more likely to happen.  I thought about lasagna a few weeks ago, knew I had most of what I needed, just needed a recipe really.  Do I have my mom's recipe or is it one of those things that's more in her head but not written down anywhere?   I also talked to her about making chicken and dumplings to get her thoughts/input since I've got bisquick and I think it would go over well here.   Just went through my "recipe book" I typed up before starting college thinking I was going to be like my sister who had moved out a year before making all these fancy things for myself for dinner.  Makes me laugh what I put in it.  Mostly desserts, some snack or side dishes and maybe a few actual meals.  Way to go Carrie from ten years ago! So here is the list (probably won't make all of these) but it sh...
Read more