
The 3 states of water
I want to express a different opinion than the current one.
Seeing water as solid, liquid, and gas does not support its unusual character.
It is helpful to view it as 3 states, without regard to whether it is solid or gas.

The 3 states are:
Intermittently connected molecules = liquid water
Completely separated molecules = Water vapor
Continuously connected molecules = Hydrogen bonded water molecules
How does this help?
- One can see the changes from one state to another; for example, continuously connected (hydrogen-bonded) water molecules can be solid (ice, snow) or gas/mist (connected water vapor molecules that support fog and cloud formation)
- Note that water cannot go directly into continuously connected (hydrogen-bonded) molecules without first changing into water vapor.
- Liquid water --> water vapor --> snow or a water vapor netting that holds air/liquid water droplets in fog and clouds.
- Similarly, ice cannot form directed from continuously connected water molecules; it has to be liquid water or water vapor to be able to transform to ice.
- Snow --> Water vapor or liquid water --> ice
Why does this happen?
It is possible to visualize the effects of different atmospheric conditions on the 3 states of water
- Temperature changes:
- create water vapor from liquid water
- Water vapor cools down to continuously connected molecules
- Pressure changes:
- Pushing water vapor molecules together will cause condensation into liquid water
- Applying very high pressure on liquid water will freeze the water
- Decreasing pressure will allow more liquid water to vaporize
- A large amount of dust particles in the atmosphere will:
- create nucleation particles for water vapor to condense into liquid
- Allow water vapor and water to freeze into ice
- Allow water vapor to crystallize as snow
Can we understand the 3 states at the molecular level?
Yes, each molecule has its personality and its electron configuration.
This will be extrapolated further in two courses: Why is water clear and transparent? and The 3 states of water: not solid, liquid, and gas.
Picture credits:
- Joao Alves. Clouds. Flickr photo-sharing, Taken on May 13, 2009.
- ravas51. IMG_2395. Flickr photo-sharing. Taken Feb 5, 2013
- Hijab, J. Diagram showing the 3 states of water and the connections between them, June 2020