A few things are mixed up here, I'll try to explain:
quote:
Originally posted by vaccination
quote:
Originally posted by Voldemort
quote:
Originally posted by mattisdada
Proper chemical and physical(wrong word i think but oh well) dont occur properly in high temperatures(and low).
erm no
it varies.
Indeed. In fact most things have more energy at higher temperatures as the particles in said object(be it a chemical, gas, piece of wood etc) move faster the hotter they are. This is why things react together when you heat them up. It's all to do with the amount of collisions per second in a reaction, as that is what causes the reaction, particles hitting together. When you heat something it's particles subsequently move faster, resulting in more collisions per second(and some of a higher force, because the particles have to hit each other above a certain speed too, but that's another story) which makes the reaction occur.
The reason reactions stop at low temperatures is because the particles slow down and cannot react as fast. When you get down to absolute zero(0Kelvin or -273.15 Centigrade) the particles are said to have stopped moving altogether(but this is impossible to achieve artificially).
Absolutely correct. But for those who are wondering now, all the above is for
chemistry only.
With computers we are talking about
electricity, which is something different than chemistry (well, not exactly, but electricity is a special property of chemistry).
With electricity the temperature should be as low as possible (in general), prefereable as close to the absolute zero point (0°K or -273.15°C) as possible.
The reason behind this is that the hotter a conductor gets, the more electric resistance it will give.(*1)
When a conductor gets close to or is at the absolute zero temperature point, the resistance will be zero. When there is no (or close to zero) electrical resistance we are speaking of
superconductors (something you've probably already heared about).
-------------
quote:
Originally posted by vaccination
Er, anyway, the reason overheating is dangerous in computers(and life in general) is not because of any chemical related issues, but simply because the heat will damage the component, eg catching fire, melting, exploding etc.
That _is_ chemistry and has _everything_ todo with chemical and physical properties of stuff though....
So, heat is also indeed bad for
damaging components. The reason for this
is exactly because of the chemical and physical properties of the components. As you said so yourself, the hotter something gets to quicker the atoms and molucules will move and the quicker they will react with others.
So, if a component gets extremely hot, it will melt, bend, warp, evaporate, explode, break down.... The chemical reactions become quicker, become more violent...
On the other hand, some combinations and bonding of materials do not react very well to cold either and it will damage the components just as well!!! So, dipping your entire PC into liquid nitrogen or putting 'dry ice' (solid CO2) on it, will damage it also for sure.
(*2)
-------------
* Both
(1) and
(2) are some of the reasons why overclockers put a special cylinder on top of the CPU to put dry ice or liquid nitrogen in, instead of putting it all over the place. In that way, components which can't tolorate extreme cold temperatures (like almost everything in the PC) wont be damaged, while the only part which needs to be cooled gets a cold shock**.
** is actually not very good either though!! Hence we speak of 'shock'. It is far better to gradually lower the temperature instead.
Then there is also the issue of condensation (another chemical reaction). When you lower the temperature of a gas, it will react with objects and form condensation. So, water vapor in the air will condens on the components. And as we all know putting electricity and water together is a bad idea, at least in this case, since water conducts electricity too.. so you can get short circuits***.
*** And that is the reason why you should
always leave an electronic device
OFF when you bring it from the cooler outside to the warmer inside. Water vapor in the room air will form condensation when it comes in touch with the cooler objects (coming from the outside). So, you should always wait a while before turning it on so that the objects can warm up to room temp and that possible condensation can evaporate again.
Thus, even if you're extatic about that new device you bought and want to try it out immediatly when you get home, do not!!! Let it 'rest' for a while before you turn it on; let the components gradually warm up to the room temperature, this is called 'acclimatization'.
Of course, the same goes for when you bring an electronic device from the inside to the outside in summer, when it is hotter outside then inside.
This also goes for laptops btw!!!!
**** I will stop linking stuff together now
/ 
