Here’s a series of emails that went back and forth about water and electricity that we thought you’d enjoy reading over (this is a question we get a LOT here at our headquarters):
“We dangled the tips of our alligator clamps in a glass jar of water & the circuit didn’t complete – why not? Do we need to add things like salt or lemon juice to make it work?”
Aurora: Ah… yes we didn’t get to that part today in our free electricity teleclass. The water molecule does not conduct electricity, contrary to popular belief… it’s the stuff floating around the water that conducts it. So, dirty water will conduct better than clean… how about salty water?
OK . . . so now college & grad school grandma (who always thought water conducted electricity) is curious. Why will dropping an electric appliance in water electrocute you? And, what about how we see in the movies how folks standing in a puddle which has a broken electric pole has dropped therein will be electrocuted?
Aurora: Great question – we actually remind people that taking the toaster in the bathtub is still a bad idea because while PURE water does not conduct electricity, every single drop on the planet has *something* in it… and will conduct to some extent. So keep the hair dryer out of the shower. Does that help? (Great questions, by the way!)
YES! This absolutely does help – learn something new every day! So, I guess by extension that the guy standing in a puddle is at risk because the water is dirty – ding, ding, ding! I just can’t wait to see Nigel wow his cousins (& his uncle too for that matter) when he explains to them why water seems to conduct electricity i.e. that the H2O molecules don’t, but the stuff in the water does. Thanks so very much for what you do. We’ll look forward to the next class. Blessings, Nigel & his Grandma
Further notes: Since electricity is the flow of electrons, as we covered in today’s class, and while yes, water will conduct electricity, it very little compared to tap or salt water. The way a liquid solution carries a charge determines the conductivity of the solution. Salt is NaCl, but when dissolved in water, it breaks apart (decomposes) into positively charged (Na+) and negatively charged (Cl-) ions which move in the liquid from one wire to the other. The Na+ and CL- float around and carry the charge, thus conducting the electricity.
Distilled water has been boiled into steam and condensed back into water, leaving behind most minerals and salts, making it more pure than tap water. Water can break into H+ and OH- just like the salt, but it really doesn’t like to do so (the covalent bonds between the hydrogen and oxygen molecules equally share electrons within the molecule itself and it does not have an affinity for electrons, so pure water does not conduct electricity where as impure water will), making it resistant to conducting electricity.
But there are loads other things, like minerals and gases, that dissolve in water very easily. For example, carbon dioxide will immediately begin to dissolve in water.