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Comment Re:This is going to take some work (Score 1) 106

Without reading Wikipedia, I can tell you exactly what a catalyst is, at least in the realm of chemistry. It is a substance or material which provides an intermediate state to a chemical reaction, lowering the overall energy required by that process and increasing the reaction rate.

Most chemical reactions have an intermediate stage, which is not always shown when we right the simplified reaction. For example, we might write a chemical reaction like this:

A + 2B => Z

What this implies is that 3 (1 A and 2 B) molecules "collide" with each other at the exact same instant, reacting to form Z. A collision such as this (even with many many particles) is so unlikely to occur that for practical purposes it basically never happens. In reality there is an intermediate state, i.e. the reaction takes place in more than one stage, perhaps like this:

A + B => Y
Y + B => Z
or
A + 2B => Y + B => Z
                                        ^intermediate state

See, here we don't have the problem of more than 2 molecules colliding at a time: A collides with B, producing Y, then Y collides with another B, producing Z.

Often the intermediate state is at a higher energy than the initial state (i.e. you must introduce energy into the system*). Catalysts provide alternative intermediate states (C = catalyst):

A + C => X
X + B => W
W + B => Z + C (Note: in this process our catalyst is completely recycled**)
or
A + 2B + C => X + 2B => W + B => Z + C
                                                    ^----------------^intermediate states

Although we have added an extra step to our overall reaction, it (presumably) takes far less energy to reach these states than the original state in the first reaction.

*This is true for all non-spontaneous reactions, whether they are exothermic or endothermic. This is why simply putting methane and oxygen together is not necessarily enough to produce combustion; you must introduce a source of energy, like a spark.

**This is not always the case, but an example showing this is much more complicated (actually any real-world example is very complicated, which is why I didn't bother).

Comment Re:LibreOffice (Score 1) 203

LibreOffice is actually what I use, because I don't have to use it very often (10 times per year). For that, I don't want to pay for MS Office and I have moved away from piracy as I've gotten older. I probably still have a cracked Office 2007 on a DVD around here somewhere...

Honestly, it's fine as long as you don't have to use it that often, e.g. when someone insists on sending you .doc/.docx files. But I imagine the city of Munich has to use it quite a bit more than I do. If Office-related stuff is a regular part of your job, invest in MS. Frankly, it's one of the few things they do better than everyone else.

I don't see what relevance Notepad.exe has to this conversation.

Comment Re:Easily defeated... (Score 1) 56

No, C: if the WiFi circuit isn't powered, there is no MAC address sent, period. If you need to confirm that WiFi is truly off, just compare the power consumption of the phone on vs. off.

Good luck with that. The WiFi is such a piddling amount of the draw that it may not even show up in the breakdown at all.

Comment Re:Unlimited?! (Score 1) 37

unlimited
adjective
        not limited or restricted in terms of number, quantity, or extent.
        "the range of possible adaptations was unlimited"
        synonyms: inexhaustible, limitless, illimitable, boundless, immeasurable, incalculable, untold, infinite, endless,
bottomless, never-ending

Comment Re:Unlimited?! (Score 1) 37

Has the rest of the world broken the laws of physics? Due to finite bandwidth and finite time no plan could ever be unlimited.

If you understand Channel Capacity then you'd know that even with infinite bandwidth you can't transmit infinite data unless you also have an infinite signal-to-noise ratio.

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