Descent into Insanitz Because of a Kezboard

So, zou maz notice that something about this looks a little bit different.  When I first got to Germanz, I bought a cheap kezboard because I find it reallz uncomfortable to use mz laptop’s kezboard.  Being in Germanz, I naturallz bought one with a German lazout. Although the German kezboard shares manz commonalities with the American lazout, it definitelz has its differences, one of which is that the z and y kezs are swapped in position.  To avoid annozing us all too badlz, Iäm (ä is also where ‘ is on an American kezboard) going to go ahead and switch back into the American lazout. Just an editorial note for those not in the know: the layout of a keyboard can be changed in Windows to match that of whatever language you want.  The letters on the face of the keys are obviously not different, but what comes out when you hit the key is changed according to what language you have selected.

I learned most of the differences between the two pretty easily, since my brain interpreted so many of them as “new”, meaning I didn’t have to first unlearn and then relearn things, just acquire new things.  What has driven me to madness though, is this whole y and z thing.  When trying to type in English with a German keyboard, I constantly had to go back and replace the z with a y in pretty much every case.  For example, I want to type the sentence “Hey what are you doing?”  In the German layout, it comes out like this, “Hez what are zou doingÄ”.

Why catalytically splitting water doesn’t work

Suppose we wanted to develop a new catalyst to solve our energy problems. All it needs to do is take water and split it into hydrogen and oxygen, then we can burn those products and use it to power things. This process is endothermic, so the energy will have to come from *somewhere*. Well, why can’t it come from the air around our system, for example? We just make the air colder, and with global warming, that is something we don’t mind at all!

Energy + 2 H₂O_(g) –> 2 H₂ +O₂

The reason for this ultimately doesn’t have anything to do with catalysis. A catalyst reduces the activation energy of the process, but it *cannot* make any non-spontaneous process into a spontaneous one, meaning a catalyst cannot affect the value of the equilibrium constant of a system. Catalysis affects nothing but the RATE of how quickly a system reaches equilibrium. (see http://en.wikipedia.org/wiki/Activation_energy for details)

Based on the concept of Gibbs free energy, the splitting of water into hydrogen and oxygen at 298K is a non-spontaneous process because the ΔG_rxn is positive.

2 H₂O_{(g) –>} 2 H₂ + O₂

The Gibbs equation:

ΔG_rxn = ΔH_rxn – TΔS_rxn

ΔH_f for water = -241.8 kJ/mol

ΔH_f for H₂ = 0 kJ/mol

ΔH_f for O₂ = 0 kJ/mol

ΔSfor water = 188.7 J/mol·K

ΔS for H₂ = 130.6J/mol·K

ΔS for O₂ = 205J/mol·K

ΔG_rxn = ΔH_rxn – TΔS_rxn

ΔG_rxn = ((0+0)-(-483.6kJ/mol)) –298K·((205+2·130.6)-(188.7))J/mol·K

ΔG_rxn = 400.9kJ/mol

Since ΔG_rxn is positive, the reaction is not spontaneous under those conditions, meaning energy must be forced into the system. However, since the ΔS_rxn component is positive, increasing the temperature will eventually cause the process to become spontaneous as the entropic effects become dominant over the enthalpic effects. For this process, one could expect to see that occur at around a temperature of 1740K. So, if we made an oven that hot, we could do this process, theoretically. The problem, however, is that we have to heat the oven, something which requires a lot of energy. At best, the efficiency of the process breaks even exactly (speaking theoretically, within the bounds of thermodynamics). Realistically, this would be insanely useless.

The ultimate answer to this question is then, there cannot be a catalyst which simply “makes” water turn into hydrogen and oxygen under these conditions because that process is thermodynamically unfavorable. The equilibrium is the controlling factor, not catalysis. It is this reason why the process cannot simply draw energy from the air to make it happen. In short, the answer for this question is basically the 2^nd Law of Thermodynamics.

After writing this post, I feel it is safe to say: Science. It works, bitches.

Note: for any of you who don’t find your way here from Reddit, here is why I wrote this post: http://www.reddit.com/info/6nct8/comments/