There are 180 degrees between freezing and boiling because there are 180 degrees between north and south. Some oxygen molecules help fires burn while others help make water, so sometimes it's brother against brother. When they broke open molecules, they found they were only stuffed with atoms but when they broke open atoms, they found them stuffed with explosions. Weather You can listen to thunder after lightning and tell how close you came to getting hit. If you don't hear it, you got hit, so never mind.
Clouds just keep circling the earth around and around.
There is not much else to do. Water vapor gets together in a cloud. When it is big enough to be called a drop, it does. Humidity is the experience of looking for air and finding water. We keep track of humidity in the air so we won't drown when we breathe.