Electrons are reactive guys when they're on their own, and tricky to isolate. If you take a bit of fur and rub it on some amber, you end up with a surplus of electrons, but they won't hang around long (the reason I mention amber is because this is what the Greeks used - the word electron comes from the Greek for amber). This is kind of cheating, though, you just have a surface with surplus electrons. Actually isolating them is tricky. If you're a poor scientist like me and use a CRT you found by the Dumpster, your monitor has an electron gun, and you actually have some ephemeral isolated electrons that are accelerated through a vacuum before hitting the screen. Not for long, though.
If you really need some isolated electrons, the closest you'll get is a solution of them. You can make a relatively long-lived one, bizzarely:
The "solvated electron" can result from the reaction of an alkali metal (usually Li, Na, K) with liquid ammonia (not the stuff you buy at the grocery, the condensed gas that farmers and meth labs use. Here, you end up with an odd situation - you have a fairly stable solution of alkali cation (i.e., Na+) and electrons (e-) in ammonia. And it's blue!
The ammoniacal solution electrons is sufficiently stable to use as a reagent, as in the Birch reduction. These odd ducks can even exist as transient species in water, however, and have attracted the interest of physical chemists for years.
I'd love to hear from anyone who's done work on them.
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My Organic Chemistry professor Leroy 'Skip' Wade once told us that a diagram in his text book of an atom was incorrect because they had colored the cartoon such that the electrons were purple and "everyone knows that electrons are blue".
Solvated electrons are stable in water ice, at least at liquid nitrogen temperature. If you expose ice to gamma rays at 77 K, it comes out dark blue/black. (You can calculate the color treating the electron as a particle in a box). As you let it warm up, it reaches a temperature where the electrons become sufficiently mobile to recombine and the color vanishes very quickly.
More fun comes if you mess with crown ethers and cryptands, like anions of alkali metals
If you use the appropriate cryptand to trap Na+, you are able to isolate bizarre solids with a negatively charged Na like [Na(crypt)]+Na-. They are called "sodides" and are stable to up to -10�C. Elektrides are also known and contain cation-electron pairs, e.g. [Cs(crypt)]+e-.
Here's a page with a video clip of this in action. I was surprised by how intense the blue was--I was expecting a sort of light sky-blue, but it's very dark, almost indigo.
I did Birch reductions of various imines as an undergrad. It was really the first non-classwork reaction I did, outside of the imine syntheses, which were all "pour together and precipitate".
I recall first seeing the deep blue color. It made me feel sort of like a wizard doing something otherworldly, with the dry ice and ammonia and sodium, and the metal dissolving into an almost black blue. It irritated me when the flask frosted over. I kept rinsing it with solvent to be able to see it. I probably stared at that reaction more than any I've done.
I went on to do a PhD in chemistry, and have seen some pretty cool stuff, but nothing I have done since has ever had that kind of emotional impact.