Science Buddies: "Ask an Expert"

I am doing the revised Rainbow Fire Project i found while rummaging through the forums, and i have a problem, i cannot get the cupric sulfate or the lithium chloride because they are outrageously priced and my parents refuse to buy them. That leaves me with the Boric Acid and the Table Salt [which i already have]. They work good! But, i can't show up and have done my project on only 2 chemicals! Please tell me about any affordable chamicals that i can find easily!

Thank you for any help you may give me,
wizkid86

P.S. PLEASE help me!!!!!!!!

Hi,

Cupric sulphate is also known as copper sulphate. It is probably sold for a reasonable price in your local hardware store as a remedy to discourage tree roots invading your sewer pipes.

My general advice would be to talk to your science teacher, especially a chemistry teacher. He/she might be in a position to sell you a rather small amount of the chemicals you need for a very small amount of money. If that does not work enlist one of your parents to accompany you to the local drug store and talk to a pharmacist. They sometimes have nonprescription chemicals on hand they can sell, though they may require your parent to sign a register to get them. In some cases they can special order a chemical for you from their suppliers. You should also look in the grocery store carefully as they also stock some chemicals for treating pools, cleaning sewers, and discouraging insects. You may have to read labels carefully to discover the ingredients of the products. You should be able to discover a source of Epsom salt this way, also calcium sulphate (aka Plaster of Paris). If you still have trouble get creative with the yellow pages or internet. You will find pool supply stores stock some chemicals for water treatment and hobby shops may carry some things. In the San Francisco Bay area there is a store called Peninsula Scientific in Palo Alto that for many years went out of their way to help in situations like this.

Do you know any chemists? Ask around. Sometimes networking will turn up someone who happens to have a little of what you want - for your purposes I suspect you need less than a gram of each chemical. You can also try to meet professors at local college or university chemistry departments who might be sympathetic and be able to help.

Way back in the dark ages of my youth I successfully used all these strategies to supply my basement chemistry lab and science fair project needs.

Good luck!

Barrett Tomlinson

Copper Sulfate is available at Ace hardware as Rooto Copper Sulfate Root Killer in a 2 pound container for about $16 plus sales tax.

In most cases, the predominant flame color comes from the metal ion. You might try Lithium Carbonate which is used in fluxes for welding aluminum. Do you know of somebody who does welding that might give you a small amount of various fluxes?

Hi - I see that Barrett and Craig have given you some good alternate suggestions. I checked the project materials listing... and followed the links for the two chemicals you noted to check on the prices. (Unfortunately - shipping adds a good bit to the price!)

I'm posting a link to the Science Buddies project idea here for anyone else that visits the thread:

Rainbow Fire
https://www.sciencebuddies.org/science- ... p058.shtml

Let us know what else you try!

Amy
Science Buddies

Okay, thanks guys for helping me out!
I will get the new materials soon and post how it turns out!

Thanks again,
Brad

Do you know what color that the Copper Sulfate (Roebic K-77 Root Killer), Aluminum Sulfate, and the Calcium Carbonate (Plaster of Paris) are supposed to burn?

My Results:

Roebic K-77 Root Killer (Copper Sulfate) -- spots of green and purple, and at the end, the entire fire turned green

Aluminum Sulfate -- spots of green and purple, and at the end, some of the fire was dark red

Plaster of Paris (Calcium Sulfate) -- some of the fire was yellow, and more towards the end, i saw some shoots of red coming up

Thanks,
Brad

My expectation of copper sulfate oxidation would be blue/green. I'm not sure where the purple came from on this one.

My expectation of aluminum sulfate would be a silver/white or colorless.

My expectation of calcium sulfate would be predominantly brick red (orange/red); however, calcium has some violet, blue, cyan, green, yellow, orange and red spectrum lines.