Why can homonuclear molecules be gasses at STP, but be liquids when they are combined?

Question

For example, H2O.

In: Chemistry

Answer 1

The behavior of a bulk material depends heavily on how its molecules interact with each other. How molecules interact depends a lot on the positioning of bonds and types of bonds within those molecules. In homonuclear molecules, the bonds tend to be symmetrical and thus no dipole forms. Dipole is where one atom becomes more negatively or positively charged than the other, and this causes the whole molecule to behave like an electret (like a magnet but for electrostatics instead of magnetism). These magnet-like molecules are much more sticky to one-another than non magnet-like molecules of similar size.