The Cool Blue Light of Luminol

[gusgus1229]

Aside from making a camera, is it possible to make a good enough luminometer for the chemiluminescence reaction.

[tdaly]

Hi gusgus1229,

What you need is a way to either count photons directly or measure the current they induce. The articles I linked to describe some ways of doing that. If you want to build "good enough" luminometer, you are going to have to some digging on your own. Draw up some schematics, do some of your own research into the components involved and how they work. We can help you, but we can't do your work for you.

[LizetteN]

Hello! I have a question that why is answering the question 'how would temperature will affect how long the blue light is produced?' important?

[tdaly]

Hi LizetteN,

The effect of temperature on chemical reactions is very important. This project lets you see how temperature affects one particular reaction, but you can apply the same concept to all sorts of things. The rates of most chemical reactions exponentially increase with increasing temperature. This means that glow sticks "burn out" faster at higher temperatures and baking soda and vinegar react faster at higher temperatures. On a more practical level, the rates of metabolic reactions are also sensitive to temperature.

[kberg2000]

Hello!

I'm conducting an experiment on the effects of temperature on the brightness of luminol, and have a few questions about it.

1) Do you have any recommendations for levels of my independent variable?

2) Is it necessary to take multiple pictures for one trial, or can I just take one at the same time for each?

3) What would the best exposure be to take a picture in a dimly lit room?

Thank you!

[tdaly]

Hi kberg2000,

The procedure in this project idea has suggestions for how to vary your independent variable. It also has a very clear procedure in general:

https://www.sciencebuddies.org/science- ... p078.shtml

The procedure in this project idea also tells you when to take pictures during the experiment. As far as lighting for the photos go, you will have to play around with the camera you are using to get the settings adjusted right. Generally speaking, you can increase the brightness of the picture by using a longer exposure time, increasing the ISO, or opening to a wider aperture.

[LizetteN]

Hello Terik!

I'm so sorry it was really really late when I saw your reply, but I want to thank you a lot. it really helps me. thank you and sorry again .

[2shin7]

HI!

Ahmm can you please explain to me what Luminol is and what its compounds are? Can you experiment with other types of chemicals to make Luminol react? THIS IS VERY IMPORTANT DO YOU LIVE IN CLOVIS OR NEAR FRESNO, CA????

[tdaly]

Hi 2shin7,

Luminol is a molecule with the formula C8H7N3O2. Yes, multiple chemicals (specifically oxidants) will react with luminol and create luminescence. You can read more about luminol here: https://en.wikipedia.org/wiki/Luminol.

All interactions between Experts and students must remain on the Ask an Expert forums, so I'm not sure whether people will tell you where they live.

Post back if you have other questions!

[2shin7]

Hello Terik!

Do you know if there are experiments showing how to do these stuffs cause my partner and I can't find anything. I was wondering if we can use a NO BLOOD project cause it will be a hard thing to do, so yeah.

THANKS A LOT!

[tdaly]

Hi 2shin7,

This Project Idea describes how to do an experiment about luminol - no blood needed

https://www.sciencebuddies.org/science- ... p078.shtml

Post back if you have questions.

[2shin7]

Hello Terik!

yeah it does not include blood but what if we want to research about how much iron should we put with the Luminol or can we even do that? Can we even substitute blood with water that has the same amount of iron in it as blood does. This is very confusing and hard please explain if we can even do this.

Sincerely,
Shin

[tdaly]

Hi Shin,

What, exactly, is the hypothesis you are testing? What is the scientific question you are trying to answer. The more details you can provide about these things, the better we will be able to help you.

The Cool Blue Light kit uses copper, instead of iron, as the catalyst for the chemiluminescent reaction. It's probably possible to devise a set of reactions that uses some sort of other iron compound as the catalyst, but that I would need to look at the reaction chains more thoroughly. Depending on what question you are trying to answer/hypothesis you are trying to test, it might not be necessary to go down that road. I look forward to hearing more details about what you are trying to do.

Post back with details (the more the better), and we'll go from there.

[2shin7]

Hi Terik!

Well our hypothesis is, "If we add more iron to the water, then we will have more luminescence." I don't know if this is it really, because we haven't decided yet. If this helps, please respond.. If it doesn't please suggest one. Thank you so much!

Sincerely,
Shin

[tdaly]

Hi 2shin7,

Your hypothesis sounds plausible. I would encourage you to read up on "limiting reactants", particularly if you have had/are in a chemistry class. Here are two good resources about limiting reactants:

http://chemwiki.ucdavis.edu/Analytical_ ... g_Reagents
https://www.khanacademy.org/science/che ... 2sY2aaKFww

Think about how this concept might influence the outcome of your experiment.

I *think* you should be able to replace the copper sulfate with ferrous sulfate in the experiment. If you do so, then iron2+, instead of copper2+ will be the catalyzing ion. However, I'm going to have another Expert look at that and make sure nothing else is interfering with the reaction. Please note that copper sulfate and ferrous sulfate have a health hazard rating of 2, so be sure to check with your teacher about how to handle these compounds. You should also read and follow an MSDS, like this one:

http://www.sciencelab.com/msds.php?msdsId=9924056