Sunday, September 9, 2018

theoretical chemistry - How many molecules does it take to have a phase?


A single molecule can't be solid, liquid or gas. It's just a molecule. A mole of something can be any of the three. So, how many molecules does it take for phases to be meaningful?


I realize that this may depend on the molecules in question. The minimum number that can form a solid might depend on the configuration that molecules adopt when solid. The smallest crystal of a lattice for example. How about a gas though? Can two molecules be called a gas if they exist under conditions where a larger quantity of the same moiety would be in a gaseous state?


In short, can a minimum number of molecules necessary to adopt a particular phase be defined?




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periodic trends - Comparing radii in lithium, beryllium, magnesium, aluminium and sodium ions

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