New to home experiments. What one's shall I do?

[weeeman]

Well I have always had a fasination chemistry and how it works and believe me I have many many questions that i will be asking.

I am studying physics, chemistry and maths in A-level and will be going to study chemical engineering hopefully.

To start with I have been reading through this awsome forum and decided to ask.

What is the best reaction/s to do at home?

I have limited equiptment so please ber this in mind. Basically I am starting home experiments and would like some fun simple ones to do at home.

Thanks in advance.

 

PS. If water boils at 100degrees (dont know the degrees button) how come that when you are in the bath for example, there is steam? Clearly the water is not boiling or you would boild

[Suxamethonium]

Water boils at 100 degrees, but water is volatile below that temperature. Volatility is a measure of the ability of something to evapourate below it's boiling temperature- and this occurs because the molcules in the sample are not all the same in energy. There is a bell-curve distribution (look up statistical distribution on wiki for more info) for the energy/velocity of molecules at any given time. Most molecules will have energies around what is governed by the sample temperature, but a few molecules will be really low in energy, and some will be really high in energy. At a certain temperature, the high end of the curve will reach the boiling point of the compound, and only the molecules at or above this temperature will 'break free'. Once they leave they are no longer part of the sample and the molecules will redistribute to produce the curve again- as a result the sample slowly evapourates over time. The hotter the sample, the more of the curve will sit past the bp, and more molecules will evapourate at once (increasing the rate of evapouration)- which can become noticable as steam in the case of a bath. This also explains why puddles can"dry up". And the same prinicple explains why washing dries faster in a warm, dry wind rather than a still day of the same temperature (the wind mechanically picks up the water molecules higher in energy and sweeps them away).

[weeeman]

Wow. That was very useful and I understood it all, so thank you for making it understandable and thanks for explaining. I will definately look up the graph to understand it more.

Much appreciated

Edited February 25, 2012 by weeeman