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Everybody knows you can produce electrostatic charge rubbing two different materials together. But have you ever smelt e.g. at the plastic after charging it? There actually is a distinct electrostatic charge smell :-) While normally smelling involves the transport of molecules, what you are smelling here, is the electric field itself, or do you? What is happening?

wnrph
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  • "Smell of electric field itself" , is a funny thought, but not possible. Think of Faraday cage, Your (everyones) nose is one. Did You ever smell Ozone? This is my first guess (BTW a molecule!) Of course other reaction products from the plastic could be the cause, but then different kinds plastics should smell different. – Georg Sep 17 '11 at 17:58
  • @Georg The charge could be picked up by molecules and get inhaled with them. / Why should ozone form more easily in an electric field? – wnrph Sep 17 '11 at 20:52
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    @aristoex: Please read about ozone formation at least in wiki or the like. The absorbed charges are a very common thing called air ions, they are around at any time at least in open air, they do not smell. In general: Your tendency to speculate instead of getting information is disgusting. – Georg Sep 17 '11 at 21:05
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    @Georg When trying to explain things, doesn't everyone start out with speculations? There's nothing wrong with it if you're open to falsifying them. And getting information is exactly what this site is about. – wnrph Sep 17 '11 at 21:20
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    @Georg Regarding your judgements on other people's character: you might want to read the FAQ again. – wnrph Sep 17 '11 at 21:45
  • The glass of our old CRT television would also get a distinctive smell. I suppose that is the same. – Kris Van Bael Sep 18 '11 at 07:22

2 Answers2

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You smell ozone ($\mathrm{O_3}$, from the Greek word ozein for "smell"), and maybe nitrous oxide - the reaction product of oxygen and $\mathrm{N_2}$.

There is a nice description of the formation and action of ozone at this link. Briefly:

Oxygen molecules ($\mathrm{O_2}$) can be dissociated (broken into atoms or ions) by either UV light, or electrical discharge. The resulting radicals are extremely reactive, and will react with other molecules. Reacting with oxygen, they will form ozone; reacting with nitrogen, they will form nitrous oxide. When you inhale ozone, it reacts with the water in your nose and forms hydrogen peroxide. The combination of that, and the nitrous oxide, is what you smell near photocopiers (which, if they use the Xerox process, operate with a high static voltage inside) or anywhere that you have high voltages and corona discharge (as you will get when rubbing dissimilar insulators together).

It's possible you also smell other things - but ozone is the one that is always present (you can sometimes smell it as a thunderstorm approaches, as the local electrical field builds up and small discharges occur ahead of a lightning strike. While this process occurs at higher altitudes, the approaching thunderstorm is associated with vertical air currents and this transports ozone from higher altitudes to ground level.) See for example this Scientific American article

The scent of ozone heralds stormy weather because a thunderstorm's downdrafts carry O3 from higher altitudes to nose level.

Floris
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The charge on the object ionizes the air a little. I believe that you smell some combination of that and reaction products (such as ozone) from ionized air.

sevenofdiamonds
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  • are you sure about the ionization of air??? because, one can get that peculiar smell even by rubbing both arms on a dry day... – Vineet Menon Sep 17 '11 at 14:55
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    Why would a dry day have less ionization? – Ron Maimon Sep 17 '11 at 15:26
  • Charge on some surface neither ionizes or otherwise chemically alters something in the air. Chemistry starts only when that charges move, eg as sparks or corona discharges. – Georg Sep 17 '11 at 19:22
  • @RonMaimon - The conductivity/resistivity of air depends upon the humidity. Pure water does not conduct electricity, so I think that water dissolved in the atmosphere increases its effective resistivity. – honeste_vivere Apr 27 '15 at 20:32
  • @honeste_vivere no, the conductivity of moist air is much greater than that of dry air - which is why you get static shocks in winter (lower relative humidity inside as cold air outside cannot contain much moisture). See http://www.dtic.mil/dtic/tr/fulltext/u2/a199599.pdf figure 3. – Floris Apr 28 '15 at 04:08
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    @Floris that is certainly interesting and in conflict with experience… Hmmm… This makes me wonder why are static electricity experiments so much easier to perform when it is really cold and dry? Or wait, am I thinking about this backwards? Shoot, I was confusing the ability of static discharge to occur with conductivity… Sorry, I had those backwards. Thanks for catching that. – honeste_vivere Apr 28 '15 at 11:14