Naked Science Forum

On the Lighter Side => Science Experiments => Topic started by: mattmckee on 05/10/2009 10:38:36

Title: How reactive is francium?
Post by: mattmckee on 05/10/2009 10:38:36

Hi, just wondered if a) anyone new of any videos with francium in
b) does anyone know if Francium and water has ever been done - for years I've told my class it's most likely extremely reactive - show them a caesium video, then say imagin francium - and they understandably say - I can - when can I see the proof!

Cheers

Matt

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Title: Re: How reactive is francium?
Post by: Bored chemist on 05/10/2009 19:43:43

I doubt that anyon has ever got enough francium to actually see it.
It's very unstable because of its radioactivity.

Title: Re: How reactive is francium?
Post by: chris on 05/10/2009 20:03:16

Francium would actually be less reactive with water than caesium owing to quantum effects.

Have a listen to this edition of Chemistry in its Element, which we made for the Royal Society of Chemistry, and in which this question is discussed:

http://www.rsc.org/images/CIIE_Francium_tcm18-152305.mp3

Chris

Title: How reactive is francium?
Post by: daveshorts on 06/10/2009 08:57:27

I think it is relativistic effects on the quantum mechanics. Basically the inner electrons are going so fast that you need to take into account relativity to work out their energy levels, and this has knock on effects on the outer electrons making them more stable and hence less reactive.

Title: How reactive is francium?
Post by: mattmckee on 06/10/2009 19:50:50

Thanks for the replies, the mp3 file was excellent and cleared it up, also good to be able to offer my students a fuller picture and one that can make them wonder even more, lots now asking about quantum effects, so maybe the truth is better than we'd expected! [:)] [:)] [:)] [:D] [;D] [^]

Cheers

Matt