Dancing flames - aluminium and the reactivity series

When teaching the reactivity series, aluminium’s protective oxide layer can make it difficult for students to see its true reactivity in the context of metals reacting with aqueous solutions. This demonstration shows the reaction of aluminium in solutions that students are likely to have already met. With a little practice, it has the added wow factor of burning with an eerie green flame that dances in the vessel as hydrogen is evolved.
Read the article that accompanies this video in the September 2014 issue of Education in Chemistry at rsc.li/EiC514ec
This is part of the Education in Chemistry Exhibition Chemistry series: chemistry demonstrations to capture your students' imaginations: rsc.li/EiCExChem

[@notthatcreativewithnames]

I once do some experiment about CuCl2 and Al as well. I put some solid CuCl2 on the concave bottom of a soft drink can, scraped a bit. Then I put little water on that solid. The reaction is quite spectacular. The reaction eats aluminium can to the laminated layer for some small area!

[@bs140598]

Since CuCl2 was not avail to me , i used CuSo4 + HCL(dil.) to make CuCl2, pretty easy way to get CuCl2, and boom! i made the project. Since CuSO4 is blue, i made sure to put enough HCL to make it Green :D.

[@declan.fleming]

nice thanks for sharing :)

[@vijayravichander1764]

Thanks for sharing

[@samyanais1075]

Are you sure that it works ?

[@Dragonfrog74]

We' ve just tried today...its working 😊

[@samyanais1075]

@@Dragonfrog74 unfortunately I hoped if you could answer earlier but it's okay thank you so much I will try it

[@andrewhaychemistry]

Great video, thanks. My Higher class had a go today and enjoyed the flames in a dark classroom. Followed up by gettiing them to identify the two redox reactions and the oxidisiing agents. Nice segue into the location of H on the periodic table.

[@MadScientist267]

Looking for blue. The all elusive blue.

[@jyotilaxmikalmath5394]

Who discovered it

[@cheshirecats6974]

Am I able to have the balanced equation of these reactions?

[@royalsocietyofchemistry4447]

Hi There, you can read more about the reactions taking place here; eic.rsc.org/exhibition-chemistry/dancing-flames/2000045.article.

[@iamnoob9841]

Hi! I'm new to these kind of stuffs... What will happen if I put ethyl alcohol instead of sulfuric acid?

[@mauronarf]

Declan, do you know why the CuCl2 looks more greenish than the CuSO4 ? Thanks! Great demonstration :)

[@declan.fleming]

mauronarf sorry I don't get notifications on these. remember that Cl is a weaker field ligand than H2O. [CuCl4]2+ is green for example. as the concentration of Cl increases against the water you'll get more Cl ligating and the colour will be greener. Obviously works​ vice versa .. the less Cl Vs the water the more [Cu(H2O)6]2+ you'll have and the more blue. Would you agree?

[@mauronarf]

Makes complete sense. Thank you for your reply! I'll try this one soon ;)

[@mauronarf]

Ok. Tried it. The reaction worked... I couldn't sustain the flame, I went 'whoosh'. Maybe a bigger flask... Thanks! :)

[@wrynil]

@@declan.fleming I tried with Cu(1)CL and it is more green (with a yellow tint) than the used CuCl2. How come?

[@declan.fleming]

@@wrynil randomly I was looking at this already in another window this morning (following the green "engine-rich" flame just before the Starship 8 crash) .. having skimmed a lot of papers characterising copper compound emission spectra I think the only answer I'm happy with is "different proportions of Cu oxidation states in flame likely to give you different colour by emphasising different transitions" ;)

[@Mainak714]

As this produces hydrogen.. can it be safe to do in laboratory ? Any chance to explode?

[@Heisenberg-m6r]

I perfomed this experiment many times and it was OK....but it would be good to do it with a protective screen...