eli5: Why O2 and H2 are gasses but H2O is a liquid?

Question

In the same conditions of course.

In: Chemistry

Answer 1

H20 is built like a magnet (called a polar molecule). The O atom attracts the electrons of the 2 H atoms, si the O side is negative (-) and the H side is positive (+), so they tend to stick togheter and don’t want to move around so much at room temperature, so they don’t become a gaz.

O2 (same for H2) have their electrons (-) are equally tempted to go the either of the O atoms, so no side is more negative than the other. They don’t have a tendency to stick to each other, so at room temperature, the molecules move fast enough to be gaseous.

Note : Many other characteristics can make a molecule gaz or liquid (for example, the size of the molecule, bigger molecules tend to have higher evaporation temperature), this is just one of the reasons.