Question: where does liquid end and galss begin?

Stuart Mourton answered on 20 Jun 2011:

That depends on the element or substance in question. Every element has a different structure of protons and electrons, and it is this make up that dictates when the element is solid, liquid or gas. Oxygen, for example, has to be very VERY cold before it turns from a gas into a liquid, whilst Mecury, which you may have seen in chemistry lessons, is liquid at room temperature.