We make an instrument called a Proton Transfer Reaction Mass Spectrometer. It's not our very own unique idea. In fact, it's a pretty well-established technique. The gist of the technique is that we (via magical electrical means that aren't important right now) take a load of water, and add a proton to every water molecule. Then we mix the water-with-a-proton (also known as protonated water or "hydronium") with the interesting stuff we want to analyse. The protonated-water then, very generously, gives up the extra proton to the interesting stuff. Hence "proton transfer".
Here's some little diagrams for you. Because diagrams make the world a better place.
Water-with-a-proton meets interesting stuff |
Interesting stuff now has protons |
You may have spotted that I have indicate the protons with a little "p", for proton. Now, obviously, I know that you are all beings of supreme intelligence, but just for now I'm going to assume you know about as much as my customers appear to know.
Can anyone tell me anything at all that they know about protons? Anything perhaps about what charge they have on them? Yes, that's right, they are positively charged. (Are you sure? Yes, I'm positive!)* So I think it would fair to expose you to a little bit more science now (don't panic, stay with me!). One way of looking at a proton is as a positively-charged Hydrogen ion. OK, now non-chemists might think that's a bit weird, but Hydrogen is the simplest element there is - it's just one proton and one electron. And if you steal the electron from it, it's just a proton.
So we'll try those diagrams again, but in a more chemist-y sort of way.
Protonated, positively charged, water meets interesting stuff |
See, it's not so bad is it? Instead of a "p" I've just put a little "H+", which also has the benefit of helping our feeble little brains remember that protons are positive. (I could have put p+ for the proton, but this is chemistry, so I've put H+, because chemists prefer elements to sub-atomic particles, even when they're the same thing**).
And again:
Protonated interesting stuff |
So, I think we might have a good chance of guessing what charge our interesting stuff has, once it's laid claim to a proton. Especially now we've got the really technical diagram. Do we think it's a negative charge? No, no, we don't, do we? We think it's a positive charge. None of you delightful people would be so pig-headedly, obtusely, mind-numbingly stupid as to ask why their proton transfer reactor didn't make negative ions would you?
Who wants to guess what my customer asked me this week?
* Give me a break! There are so few jokes in physics, I have to get them in when I can.
** Yes, you're absolutely right, physicists do look down on chemists.